I have a strange issue. I have two dropdowns. When one of them is selected, based on the selected value, the second dropdown automatically fills. Iam filling both the dropdowns using Ajax callbacks from JQuery. 

The problem iam facing is iam unable to set the index position of the second dropdown. I have tried all the methods to set, but unable to succeed. What happens is I can see that the value is changing in the second dropdown for a second, but later it immediately resets to index 0. I have tried the below methods to set the index position:

$("#<%=ddlDepartment.ClientID%>").val('test');

$("#<%=ddlDepartment.ClientID%>option:eq(3)").prop('selected', true);

$("select#ContentPlaceHolder1_tabOfferDetails_tbpnlCandInfo_ddlDepartment>option:eq(3) ").prop('selected', true);

Can you guys please help me? I don't know where am doing wrong.

Thanks & Regards,

Srikanth