The answer is hyperactive. The word hyperactive refers to extremely active or abnormally active. Hyperactive is the adjective form of hyperaction. Hyperactively is the adverb form. The work inactive refers to being not engaged or not working while the word reactive refers to the acting in response to a situation.
This is True. If you are referring to an author about whom you had previously written in the paragraph, you are allowed to omit the name from the parentheses.