A scientist bred fruit flies in two separate containers with different food sources for many generations. When she put the fruit flies from the two containers together again, she observed that the flies preferred mates raised on the same food. Which conclusion can the scientists draw?​

I've seen this question before, and I don't know if you're looking at the multiple choice version. If you are, I believe the answer is d)Fruit flies prefer mates adapted to the same food source.

Explanation:

The four options are these:

A. Fruit flies mate randomly regardless of how they were bred.

B. Fruit flies can adapt to eating different food sources.

C. Fruit flies prefer the container where they were bred.

D. Fruit flies prefer mates adapted to the same food source.