Identify the grammatically correct passive construction:

Which of the following sentences correctly uses the past perfect continuous form of the verb "to be"?

What is the function of "to be" in the sentence: "To be or not to be, that is the question"?

What is the voice and aspect in the sentence: "He has been being questioned by the committee"?

Which sentence shows a correct use of the verb "to be" in the future perfect passive?

Which sentence correctly uses "to be" in a causative construction?

In formal academic writing, which is the best alternative to avoid repetition of "to be" in the sentence: "The result was that the solution was incorrect"?