Topic: Degree of Comparison,

Best Answer Explained in Below-:

The sentence "He is the (bad) boy in the class." requires a superlative adjective to convey the intended meaning. In English, when we want to describe one member of a group as having the highest degree of a certain quality, we use the superlative form of the adjective. The base form "bad" needs to be modified to communicate that he is the most "bad" among his peers.

Among the provided options:

- A) wors: This is not a valid word in English.
- B) better: This is the comparative form, used for comparing two items, not for establishing the highest degree within a group.
- C) worst: This is the correct superlative form of "bad," indicating that he is the most "bad" boy in the class.
- D) bad: This is the base form, which does not convey superlative meaning.

Thus, the correct choice is C) "worst," as it accurately completes the sentence to indicate that he stands out as the most troubling or problematic boy in the class compared to all the others.