I believe the answer is C. Both A and B.
The sentence “Carl, you both lie and act like a terrific
monster!" my little brother declared” does not use parallel
structure correctly.
Parallel structure<span> <span>(also
called parallelism) is the repetition of a chosen grammatical form within a
sentence. By making each compared item or idea in your sentence follow the same
grammatical pattern, you create a </span>parallel<span> construction.</span></span>
The correct answer between all
the choices given is the second choice or letter B. I am hoping that this
answer has satisfied your query and it will be able to help you in your
endeavor, and if you would like, feel free to ask another question.