Answer:
B. Because she smiled at me.
Step-by-step explanation:
Phrase is a group of words which forms a unit in a sentence.
Phrases are classified into noun phrase, verb phrase, adjective phrase, gerund phrase, infinitive phrase.
In the following sentence: the lost dog was found by the police.
The lost dog is a noun phrase
Was lost is a verb phrase
By the police is a prepositional phrase.
Option B is not a phrase, rather it is a clause because it has connector, subject and verb.