I want to test the ability of students to read a passage and answer questions about it. Could you please come up with a good question for the passage "Artists contributing to this format include mainly soft rock/pop singers such as, Andy Williams, Johnny Mathis, Nana Mouskouri, Celine Dion, Julio Iglesias, Frank Sinatra, Barry Manilow, Engelbert Humperdinck, and Marc Anthony."? 

What are two examples of female soft rock/pop singers?