Explanation:

- The given word is "hefty." It means large, heavy, or substantial in size or amount.

- Option 1: Handsome - This word generally means good-looking; in some contexts, it can mean substantial or generous, particularly regarding sums of money, making it not a direct opposite of "hefty."

- Option 2: Generous - Related to kindness and willingness to give; not contrary to "hefty."

- Option 3: Slight - Refers to something small in size, degree, or intensity. It directly contradicts "hefty."

- Option 4: Liberal - Often means open-minded or generous; not the opposite.

- The correct antonym for "hefty" among the options is indeed Slight.