Of all the inventions,（）was probably the most important for civilization.

A．Thomas Edison was always interested in science and inventions, and he invented many important things
B．Thomas Edison could not keep a job
C．Thomas Edison worked day and night on his experiments
D．deaf people make good inventors because they can focus without the distraction of spoken conversation

A．He became a telegraph operator, a newsboy, and then got his first patent.
B．He became a newsboy, got his first patent, and then became a telegraph operator.
C．He got a patent, became a telegraph operator, and then became a newsboy.
D．He became a newsboy, a telegraph operator, and then got a patent.