He is really good _______ English.
Correct Answer: C (at)
In this sentence, the correct preposition to use is “at.” We use “at” to describe someone’s level of proficiency or ability in a particular subject or activity. For example, “He is really good at playing the guitar” or “She is really good at math.”
Difference Between “In,” “On,” and “At”
|in||used to indicate a location within a larger space or a general time period||
|on||used to indicate a surface or a specific date or day||
|at||used to indicate a specific point in time or a specific location||