Presenting a Female Empidid Fly with a Prey Item Such

Multiple Choice

Presenting a female empidid fly with a prey item such as an insect, wrapping a prey item in an elaborate cocoon, or presenting an elaborate, but empty, silken balloon all seem to revolve around the fact that

A) a male may easily become a meal rather than a mate for the predacious female.
B) males can demonstrate their potential quality as a mate by presenting a nuptial gift.
C) some female empidid flies are less intelligent than others and don't realize they are being fooled.
D) some female empidid fly species need more protein than others.