Which words in the sentence are the prepositional phrase?
morning came, and i smelled the aroma of pancakes.
a. and i smelled
b. of pancakes
c. morning came
d. the aroma
last

The correct answer is B, "of pancakes". A cannot be correct because it is a sentence, C as well, D is a noun phrase, so the only possible solution could be B. A prepositional phrase consists of a preposition (in this case, "of") and a noun (in this case, "pancakes").