The solution to the problem of making the lock stitch on a sewing machine is said to have been inspired by a nightmare.

A．He is applying for a job at a summer camp.
B．His telephone is out of order.
C．He is writing a character reference for Ben.
D．He is replying to Ben’s letter.

A．Seven-thirty.
B．Eight o’clock.
C．Seven o’clock.
D．Six-thirty.