Justify each step in the following (partial) proof of that (pq)(rq) and p(rq) are equivalent by using a series of logical equivalences. Choose the most important reason for each step by filling in the blanks with A, B, C, D,E, or F. They stand for the the following equivalence rules: A. Implication, B. Commutative laws, C. Associative laws, D. Distributive laws, E. de Morgan's laws, F. Double negation. (pq)(rq)(pq)(rq)pqrqprqqpr(qq)prq(Idempotent)p(rq)