"based on the information provided about the regulation of testosterone secretion, propose a testable hypothesis to explain how trenbolone acetate caused frank's testicles to shrink."

The trenbolone acetate caused frank's testicles to shrink because the steroid is taking over the job of the testes so the testes don’t have to do as much work making them less muscular. Trenbolone acts in the same way that testosterone acts, but the esterified form of the hormone is approximately 3 times more potent than the naturally occurring hormone; that is, 3 times more testosterone is required to produce the same effects as a particular amount of trenbolone acetate. Some of its trade names are Trenbol, ester derivative and synthetic steroid. Its chemical structure is similar to that of testosterone, the naturally occurring hormone that is produced by the testicles.

the answer to this question is a