TEZPUR 2025 — English PYQ

The correct answer is (d) at.

In English, when describing someone's ability or skill level in a particular subject or activity, the idiomatic expression used is "good at."

• "Good at": Indicates proficiency or skill. For example: "She is good at mathematics."

• "Good in": Generally used when referring to performance within a subject or a specific academic environment, but "good at" is the standard collocation for innate skill or ability regarding a specific task.

To represent this grammatically, we can look at the relationship between the subject ($S$), the adjective of skill ($A$), and the object ($O$):

$$Sentence=S+\text{is}+A+\text{at}+O$$

Substituting the components from your example:

$$\text{"She"}+\text{"is"}+\text{"good"}+\text{"at"}+\text{"numbers"}$$

The preposition "at" is required to link the adjective "good" to the skill-based object "numbers." Using other prepositions would result in:

$$P(X)=\{\begin{array}{ll}\text{Correct,}& amp;\text{if }X=\text{at}\\ \text{Incorrect,}& amp;\text{if }X\in \{\text{in, on, by}\}\end{array}$$