As is known to us, all the (burn) （） of any fuel requires oxygen.

A．Customer and waiter.
B．Wife and husband.
C．Boss and clerk.
D．Father and daughter.

A．11 p.m. of that day.
B．11 a.m. of the previous day.
C．11 p.m. of next day.
D．11 p.m. of the previous day.