Answer:
The correct answer is b) speaks English very fluently.
Step-by-step explanation:
The sentence is talking about the father's ability to speak English. The adverb "fluently" is used to describe how well he speaks English. In this case, "fluently" is an adverb that modifies the verb "speaks" and describes how he speaks English. The adverb "fluently" is formed by adding the suffix "-ly" to the adjective "fluent." Therefore, the correct form is "very fluently."