下列计算正确的是 [ ]

A.a²·a³=a⁵

B.（a²）³=a⁵

C.a¹⁰÷a²=a⁵

D.2a⁵-a⁵=2

— He works quite hard.

— Maybe you don't know that he always ____ without asking for leave when he ____ in another company. [ ]

A. went to work; was

B. goes to work; is

C. didn't go to work ; was

D. doesn't go to work; is