Given a statement, generate a question such that the answer is contained in that statement.

[EX Q]: elephants have a placenta
[EX A]: What do elephants have?

[EX Q]: straightening an arm consumes energy
[EX A]: How much energy does straighten an arm consume?

[EX Q]: fly infection is established when flys enter through the skin
[EX A]:
What is established when flys enter through the skin?