Explanation:

- Jolly means happy, cheerful, and full of good humor.

- Option 1: frivolous - This means not having any serious purpose or value. It's more about being carefree, not a direct opposite of jolly.

- Option 2: capable - Means having the ability or skill to do something. It doesn’t relate to jolly in terms of mood or disposition.

- Option 3: cheerfully - Means in a happy, pleasant, or positive manner. This is similar to jolly, not an opposite.

- Option 4: melancholy - This means a feeling of deep sadness or gloom. It is the opposite of jolly, which signifies happiness.

- Correct Answer: melancholy

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