The correct answer is A. Charles Babbage.
Charles Babbage was an English mathematician, philosopher, inventor, mechanical engineer, and polymath. He is considered the “father of the computer”. Babbage is best known for his work on the difference engine, an early mechanical computer, and the analytical engine, a theoretical computer that would have been capable of performing any calculation that a modern computer can.
Dr. Hollerith was an American inventor and statistician. He is best known for his work on the tabulator, a machine that could tabulate data from punch cards. The tabulator was used in the 1890 United States Census, and it is considered to be one of the first computers.
Donald Reach was an American computer scientist. He is best known for his work on the ENIAC, one of the first electronic computers.
Ken Reider was an American computer scientist. He is best known for his work on the UNIVAC I, one of the first commercial computers.
While all of these individuals made significant contributions to the development of computers, it was Charles Babbage who first proposed the concept of a programmable computer. His work on the difference engine and the analytical engine laid the foundation for the development of modern computers.