Which is the adverb phrase in the sentence?

During a roundup, she watched cowboys on horseback at work and learned their techniques.

ADuring a roundup
Bat work
Con horseback

Verified Answer :

b. at work

Example:
In the given
statement, "The Caribbean sea is a great location for deep-sea fishing."
The phrase "a great location for deep-sea fishing" is the adjective
phrase of the sentence.

Phrases are group of words that doesn't
have a complete thought unlike clauses that can stand alone since it has
a subject and predicate whereas a phrase doesn't.
An adjective phrase is one type of phrase to describe a noun or pronoun subject in a sentence.
Also is adverb clause.