Detailed Solution:
The correct answer is “Agriculture”.
Norman Borlaug was given the Nobel Prize in (a) Agriculture.
Norman Borlaug was an American agronomist and humanitarian who is often called the "father of the Green Revolution". He is credited with developing high-yielding varieties of wheat that were resistant to disease and could grow in a variety of climates.
His work is widely recognized as having helped to prevent famines and improve food security in many parts of the world. In 1970, Borlaug was awarded the Nobel Peace Prize for his contributions to the field of agriculture and his efforts to alleviate world hunger.