[单选题]
Modern computers based on ( ) are millions to billions oftimes more capable than the early computers, which occupy a fraction of thespace. Simple computers are small enough to fit into mobile devices, an mobilecomputers can be powered by small batteries. Personal computers in their variousforms are icons of the Information Age and are what most people think of as‘computers’.
A.Central Processing Unit
B.integrated circuits
C.Hard disk
D.software integration