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TypeScript Quiz Practice
Active Recall Drill Session
← Exit Session
Question 1 of 1
medium
TypeScript
In `type FirstArg<T> = T extends (arg: infer A, ...rest: any[]) => any ? A : never`, applied to `(name: string, age: number) => void`, what does A resolve to?
A
string | number
B
string — the first parameter's type specifically, with no repeated infer to combine
C
never
D
void
Check Answer