Is the underlined phrase an adjective phrase or an adverb phrase?

The true king of the beasts is the elephant.

A.

adverb phrase

B.

adjective phrase

Of The Best is underlined

It is an adjective phrase. An adjective is any word which describes a pronoun or a noun. Hence an adjective phrase are group of words that describes a pronoun or a noun. These phrases can be placed with before the noun or pronoun or even after in a sentence.