The correct answer is: B. the
The word “the” is used to refer to a specific person or thing. In this case, the speaker is referring to a specific person in the class who is the most intelligent.
The word “a” is used to refer to an indefinite person or thing. In this case, the speaker is not referring to a specific person in the class, but rather to any person in the class who is the most intelligent.
The word “much” is used to refer to a large amount of something. In this case, the speaker is not referring to a large amount of intelligence, but rather to the most intelligence.
The word “none” is used to refer to no person or thing. In this case, the speaker is not referring to any person in the class who is the most intelligent.