Abstract type as parameter in method (.net, c#)

I have the following method which I use to fill a DropDownList-Control.

protected void LoadDropDownList(DropDownList ddl, IEnumerable<A> source)
{
    ddl.DataSource = source;
    ddl.DataBind();
}

My question is, can I make the method more abstract so that it can also tak开发者_运维问答e IEnumerables of type B?

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protected void LoadDropDownList<T>(DropDownList ddl, IEnumerable<T> source) { 
    ...

See also.

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protected void LoadDropDownList(DropDownList ddl, IEnumerable source) {
     ddl.DataSource = source;
     ddl.DataBind();
}