(41-42)    Dolphins are one of the smartest sea animals. They can understand 60 words and can make 2,000 sentences They can also detect bombs just like dogs do. The way the Navy trained dolphins to find bombs in the sea is just like the way people trained dogs. Also dolphins have excellent eyesight which can help them see very clearly in the dark water. Though they live in the sea, they do not drink sea water. If they do, they may become seriously sick.    Dolphins can live up to fifty years. But you know what? While dolphins are sleeping, they only shut down half of their brains, the other half of the brains stay awake, so they can swim and sleep at the same time.
【題組】41. What does detect mean in the reading?
(A) Try
(B) Find
(C) Cheat
(D) Throw