63（）

A．because the Japanese military had not surrendered
B．because they wanted to kill more Japanese people
C．because they wanted to show off the new weapon
D．because the atomic bomb was the best weapon

A．computer industry used to be led by the chief executive officer of IBM
B．people then underestimated the value of computers
C．humans are limited to making any predictions
D．in 1950 computer industry developed into a business applied almost in every aspect of American lives