如何确保多组单选按钮在HTML中不会相互取消选择?[已关闭]

我面临一个问题,在查看页面上显示问题和选项,并将结果提交到结果页面,检查结果是否正确。代码如下所示。

问题是单选按钮只允许选中一个。请参见下面的屏幕截图。我怎样才能解决这个问题?

[TakeExam.jsp]

<form  method="post"  action="Examprocess" class="form-horizontal">
   <div class="form-group">
     <label class="control-label col-sm-1" style="color: white"> Subject:</label>    
         <div class="col-sm-3">
         <select class="form-control" name="sub">
         <option>Select your choice</option>
        <option>cprog</option>
        <option>cpp</option>
        <option>html</option>
        <option>java</option>  
         </select>
         </div>
         </div>
    <div class="form-group">   
         <div class="col-sm-offset-2 col-sm-10">
       <input style="color:red" type="submit"  value="start exam" />
       </div>
       </div>
  </form>

[Examprocess(Servlet)]

package exam.controller;

import java.io.IOException;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import exam.DAO.CTest;


@WebServlet("/Examprocess")
public class Examprocess extends HttpServlet {
    private static final long serialVersionUID = 1L;


    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

    }


    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        String subject = request.getParameter("sub");
        HttpSession session = request.getSession();
        session .setAttribute("Subject", subject);
        if(subject.equals("cprog")) {

            CTest ctest = new CTest();
            RequestDispatcher rd = request.getRequestDispatcher("view.jsp");
            request.setAttribute("examq", ctest.getdata());
            rd.forward(request, response);

            //response.sendRedirect("view.jsp");
        }
        else if(subject.equals("cpp")) {

            response.sendRedirect("view1.jsp");

        }

    }

}

[CTest.java]

package exam.DAO;
import java.sql.*;
import java.util.ArrayList;

import exam.DTO.ExamQ;
import exam.utilities.ConnectionFac;

public class CTest {

    Connection cn = null;
    PreparedStatement ps = null;
    Statement st = null;
    ResultSet rs = null;
    ConnectionFac con = new ConnectionFac();
    String selectctest ="select * from ctest";

    public ArrayList<ExamQ> getdata() {

        ArrayList<ExamQ> arr =new ArrayList<ExamQ>();


        try {
            rs=con.getResultSet(selectctest);
            while(rs.next()) {
                ExamQ examques =new ExamQ();
                examques.setQid(rs.getShort(1));
                examques.setQuestion(rs.getString(2));
                examques.setOption1(rs.getString(3));
                examques.setOption2(rs.getString(4));
                examques.setOption3(rs.getString(5));
                examques.setOption4(rs.getString(6));
                examques.setAnswer(rs.getString(7));
                arr.add(examques);

            }
        } catch (SQLException e) {

            e.printStackTrace();
        }
        return arr;
    }



}

[ExamQ.java(getter和Setter)]

package exam.DTO;

public class ExamQ {
    int qid;
    String question;
    String option1;
    String option2;
    String option3;
    String option4;
    String answer;

    public int getQid() {
        return qid;
    }
    public void setQid(int qid) {
        this.qid = qid;
    }
    public String getQuestion() {
        return question;
    }
    public void setQuestion(String question) {
        this.question = question;
    }
    public String getOption1() {
        return option1;
    }
    public void setOption1(String option1) {
        this.option1 = option1;
    }
    public String getOption2() {
        return option2;
    }
    public void setOption2(String option2) {
        this.option2 = option2;
    }
    public String getOption3() {
        return option3;
    }
    public void setOption3(String option3) {
        this.option3 = option3;
    }
    public String getOption4() {
        return option4;
    }
    public void setOption4(String option4) {
        this.option4 = option4;
    }
    public String getAnswer() {
        return answer;
    }
    public void setAnswer(String answer) {
        this.answer = answer;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (!(obj instanceof ExamQ))
            return false;
        ExamQ other = (ExamQ) obj;
        if (answer == null) {
            if (other.answer != null)
                return false;
        } else if (!answer.equals(other.answer))
            return false;
        if (option1 == null) {
            if (other.option1 != null)
                return false;
        } else if (!option1.equals(other.option1))
            return false;
        if (option2 == null) {
            if (other.option2 != null)
                return false;
        } else if (!option2.equals(other.option2))
            return false;
        if (option3 == null) {
            if (other.option3 != null)
                return false;
        } else if (!option3.equals(other.option3))
            return false;
        if (option4 == null) {
            if (other.option4 != null)
                return false;
        } else if (!option4.equals(other.option4))
            return false;
        if (qid != other.qid)
            return false;
        if (question == null) {
            if (other.question != null)
                return false;
        } else if (!question.equals(other.question))
            return false;
        return true;
    }
}

[视图.jsp]

<div class="row">
   <div  class="col-sm-4" >
   </div>
  <div  class="col-sm-8" >

   <form method="post" action="result.jsp">

   <% int i=1; %>

<c:forEach items="${examq}" var="examq" >
  <label style="color:white">Q<%=i %>:<c:out value="${examq.getQuestion() }"></c:out></label><br>

  <label style="color:white" for="O1">O1:<c:out value="${examq.getOption1() }"></c:out></label>
  <input type="radio" name="radio" value="${examq.getOption1() }"><br>

  <label style="color:white" for="O2">O2:<c:out value="${examq.getOption2() }"></c:out></label>
  <input type="radio" name="radio" value="${examq.getOption2() }" ><br>

  <label style="color:white" for="O3">O3:<c:out value="${examq.getOption3() }"></c:out></label>
  <input type="radio" name="radio" value="${examq.getOption3() }"><br>

  <label style="color:white" for="O4">O4:<c:out value="${examq.getOption3() }"></c:out></label>
  <input type="radio" name="radio" value="${examq.getOption3() }"><br>  

  <hr>         
    </c:forEach> 


    <input type="submit" value="submit">

 </form>

  <a href="takeexam.jsp">GoBack</a>

  </div>
  </div>