<div id="div_ExistingExam" class="PopupWindow_ImageContainer">
                        
    <% Html.BeginForm("CreateNewExam", "Home", FormMethod.Post); %>

        <input type="image" 
                name="img_Delete" 
                id="method_delete"
                alt="Delete" 
                src="../../Content/Images/Image_Basket.png" 
                value="Submit" 
                title="Удалить тест" /> 
        <span class="span_FontNormal_Block25">&nbsp</span>
                            
        <input type="image" 
                name="img_Edit" 
                id="method_edit"
                alt="Edit" 
                src="../../Content/Images/Image_Folder.png" 
                value="Submit" title="Редактировать" /> 
        <span class="span_FontNormal_Block25">&nbsp</span>
                            
        <input type="image" 
                name="img_Result" 
                alt="Edit" 
                src="../../Content/Images/Image_Document.png" 
                value="Submit" 
                title="Результат теста подробно" /> 
        <span class="span_FontNormal_Block25">&nbsp</span>
                            
        <input type="image" 
                name="img_StartTest" 
                alt="Edit" 
                src="../../Content/Images/Image_Play.png" 
                value="Submit" 
                title="Начать тестирование" /> 
    <% Html.EndForm(); %>

</div>

[HttpPost]
public ActionResult CreateNewExam(string submit)
{
    return InformationView("ID элемента, который отправил запрос: " + submit);
}

<%-- НЕ работает --%>
<input type="image" 
        name="action" 
        alt="Delete" 
        src="../../Content/Images/Image_Basket.png" 
        value="Send" 
        title="Удалить тест" /> 
<span class="span_FontNormal_Block25">&nbsp</span>

<%-- работает --%>
<input type="submit" name="action" value="Send" />