Final answer:
The best word to complete the sentence is 'divertida'.
Step-by-step explanation:
The correct answer is D) divertida.
In this sentence, the adjective 'divertida' is used to describe the noun 'clase' (class). Since 'clase' is singular and feminine, the correct form of the adjective is also singular and feminine: 'divertida'.
For example, you could say 'La clase es divertida' (The class is fun) to describe a class that you find enjoyable.
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