Please explain

The ad tries to persuade the reader to subscribe to their magazine by explaining that exercising leads to the better performance of the heart and lungs, which are physical organs. It then says that the brain is also a physical organ and concludes that, therefore, exercise will also improve the performance of the brain. But, just because exercise improves the performance of the heart and the lungs, which are physical organs, does not mean that just because the brain is also a physical organ, exercise will also help the performance of the brain. The fact that the brain shares a characteristic with the heart and lungs, i.e. that it is also a physical organ, does not mean that it will share other characteristics with them. This is exactly what answer choice (E) describes: "It implies that brains and muscle are similar in one respect because they are similar in another respect." Hope that clears things up! Please let us know fi you have any other questions.

I was between C and E, ultimately picked E. However, what is the reasoning that C is incorrect? Thanks.