Answer: Many buses in the terminal are waiting to depart.
This sentence is the only one that uses a verb that agrees with its subject. In this case, the subject is "buses." The verb, which is "are," agrees with the subject because it also takes a plural form. All of the other options have verbs that do not agree with the subjects of the sentences.
Based on the given sentence above, the number of independent and subordinate clauses would be one subordinate clause only. The given group of words above only consists of a subordinate clause and does not convey a complete thought, even though the clause still have a subject and a verb. Hope this answer helps.