Question

Which of the following sentences has an adverbial phrase?

A. I am available at the moment.
B. I can be available.
C. I am available today.
D. I am available now.

Answer 1

A because there whenever you have an adverbial sentence you have something that connects to something else.
i am available connects to nothing wereas "i am available at the moment" is connecting to the sentence.

make sense?

Answer 2

The correct answer is A) I am available at the moment, where the adverbial phrase is 'at the moment'.
B doesn't have an adverbial phrase.
C and D do have adverbs 'today' and 'now', but those are single words, not phrases, because a phrase has to have at least two constituents/parts.