ASP.Net MVC: Call Controller Action on DropDownList Change (SelectedIndexChanged)

Here Mudassar Ahmed Khan has explained with an example, how to Call Controller’s Action method on DropDownList Change (SelectedIndexChanged) in ASP.Net MVC Razor. The DropDownList will be placed inside a Form and when an Item (Option) is selected, the Form will be submitted using the JavaScript onchange (SelectedIndexChanged) event handler of the DropDownList in ASP.Net MVC Razor.