This rocky canyon in the desert is not the deepest or the widest.
The adjective phrase is IN THE DESERT. It modifies the word CANYON. So, the answer is letter B.
An adjective phrase is a group of words that describe a noun or pronoun in a sentence. The adjective phrase can be placed before, or after, the noun or pronoun in the sentence.
In the above sentence, the adjective phrase is placed after the noun.
