The Average Life Expectancy of Tires Produced by the Whitney $\mu$

The average life expectancy of tires produced by the Whitney Tire Company has been 40,000 miles.Management believes that due to a new production process, the life expectancy of their tires has increased.In order to test the validity of their belief, the correct set of hypotheses is

A) H₀: $\mu$ < 40,000 H_a: $\mu$ $\geq$ 40,000.
B) H₀: $\mu$$\leq$ 40,000 H_a: $\mu$ > 40,000.
C) H₀: $\mu$ > 40,000 H_a: $\mu$$\leq$ 40,000.
D) H₀: $\mu$ $\geq$ 40,000 H_a: $\mu$ < 40,000.