A. H. Taylor and Leo C. Young were American scientists who played a crucial role in the development of radar technology. They are credited with creating the first radar system in the United States. Radar, which stands for "Radio Detection and Ranging," is a technology that uses radio waves to detect and locate objects. It became essential during World War II for various applications, including aircraft detection and navigation. The work of Taylor and Young contributed significantly to the advancement of radar technology and its subsequent widespread use in military and civilian applications.

The Rawatbhata Nuclear Power Plant is located in Rawatbhata, a town in the Chittorgarh district of the Indian state of Rajasthan. It is a complex that houses several nuclear reactors, including pressurized heavy water reactors (PHWR) and pressurized heavy water reactors of the Indian design. The plant plays a significant role in contributing to the electricity generation capacity of the region and the country.

The telephone was invented by Alexander Graham Bell. The correct answer is (A) Alexander Graham Bell. Bell is widely recognized for his pioneering work in the development of the telephone, and he received the first US patent for the invention of the telephone in 1876.

The invention of the railway engine is credited to George Stephenson. The correct answer is (D) George Stephenson. George Stephenson, an English engineer, is known for developing the first practical steam locomotive, named "The Rocket," which played a crucial role in the early development of railways.

In 1831, electricity became viable for use in technology when Michael Faraday created the electric dynamo. The correct answer is (C) Michael Faraday. 

Faraday's work on electromagnetic induction laid the foundation for the development of electric generators and dynamos, which played a crucial role in the generation of electric power.

The father of the Indian Space Programme is often considered to be:

(C) Vikram Sarabhai

Dr. Vikram Sarabhai, an eminent scientist, visionary, and the founder of the Indian Space Research Organisation (ISRO), is widely regarded as the father of the Indian Space Programme. He played a pivotal role in establishing and nurturing India's space capabilities. Dr. Sarabhai was instrumental in the launch of India's first satellite, Aryabhata, in 1975, marking a significant milestone in the country's space exploration journey. His vision and leadership laid the foundation for the development of ISRO and the growth of India's space capabilities, making space exploration an integral part of the country's scientific and technological advancements.

The third-generation anti-tank missile successfully test-fired by DRDO (Defence Research and Development Organisation) in Rajasthan is named:Nag