Which of the following is first generation of computer?

Which of the following is first generation of computer?

A. EDSAC
B. IBM-1401
C. CDC-1604
D. ICL-2900
Examples of the first generation computers include ENIAC, EDVAC, UNIVAC, IBM-701, and IBM-650. These computers were large and very unreliable.
EDSAC is first generation of computer.
EDSAC. The Electronic Delay Storage Automatic Calculator (EDSAC), developed at Britain’s Cambridge University, ran its first programs in 1949. It became the first stored-program computer in regular use, heralding the transition from test to tool.
Input was based on punched cards and paper tape, and output was displayed on printouts. The UNIVAC and ENIAC computers are examples of first-generation computing devices. The UNIVAC was the first commercial computer delivered to a business client, the U.S. Census Bureau in 1951.
The first generation computers used vacuum tubes for circuitry and magnetic drums for memory, and were often enormous, taking up entire rooms. The vacuum tube was developed by Lee DeForest. A vacuum tube is a device generally used to amplify a signal by controlling the movement of electrons in an evacuated space.