Choose the letter A, B, C or D to complete the passage below

Sir Isaac Newton was an English mathematician and physicist who lived from 1642 to 1727. He was the (1) of gravity. He discovered gravity in 1666 when he saw a (2) apple. He thought that there was a (3) of nature moving the apple. Newton called this force "gravity". He then determined that there are forces between all (4). This discovery is very important and has many (5) in physics.

He was the (1) of gravity