What kinds of toppings can people choose for Brussels waffles?

1. People can choose chocolate, ice cream, and fruit.

2. They can choose chocolate, ice cream, and fruit.
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Are both answers grammatical? Then, which one is a common answer.

Both are fine ... I think they are both used about equally.

Both answers are grammatically correct. However, they are identical, so there is no difference between them. In terms of which one is a common answer, it depends on personal preference. Some people may choose to have all three toppings of chocolate, ice cream, and fruit on their Brussels waffles, while others may prefer just one or a combination of some. Ultimately, it is up to the individual's taste and preferences.