What is the tense of the underlined verb?

a. future

b. future perfect

c. future progressive

d. future perfect progressive

If the underlined verb is will have been talking, in the sentence Lillian will have been talking for two hours by the time she finishes her classical music lecture, then the correct answer is D. future perfect progressive.

A would be - will talk.

B would be - will have talked.

C would be - will be talking.