C#

<asp:GridView ID="examgrid" runat="server" AutoGenerateColumns="false"
        AllowPaging="true" OnPageIndexChanging="examgrid_pageindexchanging"
        onrowdatabound="examgrid_RowDataBound">
<Columns>
<asp:TemplateField HeaderText="Exam">
<ItemTemplate>
<asp:Label ID="quesname" runat="server" Text='<%Eval(Ques_Name) %>'></asp:Label>
<br />
<asp:RadioButton ID="op1" runat="server" Text='<%Eval(Option1) %>' /><br />
<asp:RadioButton ID="op2" runat="server" Text='<%Eval(Option2) %>' /><br />
<asp:RadioButton ID="op3" runat="server" Text='<%Eval(Option3) %>' /><br />
<asp:RadioButton ID="op4" runat="server" Text='<%Eval(Option4) %>' /><br />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>

class ClassA
{
    [WantToCopy]
    public Property1 { get; set; }
    public Property2 { get; set; } // ...
}

class ClassB : ClassA
{
    public Property1 { get; set; }
    public Property2 { get; set; } // ...
}

class ClassC
{
    public ClassB { get; set; }
    public Property1 { get; set; }
    public Property2 { get; set; } // ...
}

T resp = GetClassC(); // get a pretend instance of ClassC

var types = resp.GetType().GetProperties();
foreach (var type in types)
{
    // I use this to figure out if the field in ClassC == ClassB
    if(type.PropertyType.IsSubclassOf(this.GetType()))
    {
        // I use this custom method to get the properties in ClassA that have the 
        // attribute mentioned above
        List<PropertyInfo> fields = GetFields(type.PropertyType);
        foreach (var field in fields)
        {
            // here is the problem!
            var value = field.GetValue(resp , null); // resp is ClassC
            field.SetValue(this, value , null); // 'this' is ClassA
        }
    }
}