I was never very good __ skiing as a child.

• A. At
• B. In
• C. On
• D. For

Answer: (A)

The main idea here is choosing the right preposition to show ability in an activity. In English, we say “good at” followed by the activity (often in gerund form). So the natural sentence is “I was never very good at skiing as a child.” The phrase “at skiing” is the standard collocation for expressing skill in skiing.

The other prepositions don’t fit this meaning. “In” isn’t the usual choice for talking about being skilled at a specific activity, and “on” isn’t used in this sense either. “For” would shift the meaning to something like suitability or usefulness, not ability.