***** NOT A TEACHER *****
Hello, EnglishHobby:
You have already received the answer. You should definitely use "smartly" on any test.
I wanted to join the conversation, however, because I feel that you may find the following of some interest:
1. There are two types of adverbs: the -ly adverb and the so-called flat adverb (without -ly).
2. Here in the United States, many people seem to prefer the flat adverb, at least in ordinary conversation and in ordinary writing. (For example: "Drive slow" instead of "Drive slowly.")
3. Therefore, if you hear an American say or write "She normally dresses very smart," you should remember that most American dictionaries accept "smart" as a flat adverb.
4. Important: The -ly adverb is ALWAYS needed in front of a verb: "She is usually a smartly dressed person."
5. In comparative sentences, according to many dictionaries, the flat adverb also seems more natural (at least to Americans):
"You dress smarter than I do" instead of "You dress more smartly than I do."
James