A Professor of Linguistics Refutes the Claim That the Average $\mu$

A professor of linguistics refutes the claim that the average student spends 3 hours studying for the midterm exam.She thinks they spend more time than that.Which hypotheses are used to test the claim?

A) H₀: $\mu$ = 3 vs.H₁: $\mu$ $\gt$ 3
B) H₀: $\mu$ = 3 vs.H₁: $\mu$$\neq$ 3
C) H₀: $\mu$ $\neq$ 3 vs.H₁: $\mu$ = 3
D) H₀: $\mu$ = 3 vs.H₁: $\mu$ $\lt$ 3