"Has been waiting" should be your answer. a simple predicate is the verb or verb phrase in the sentence and it usually tells what the subject does.
Answer:
d
Explanation:there is an error in parallel structure
Through many years of controversy with our late associates, the Northern States, we have vainly endeavored to secure tranquillity, and to obtain respect for the rights to which we were entitled.
Most of Steinbeck's work is set in southern<span> and </span>central California<span>, particularly in the </span>Salinas Valley<span> and the </span>California Coast Ranges<span> region. His works frequently explored the themes of fate and injustice, especially as applied to downtrodden or </span>every man protagonists<span>.</span>
