The word “cumulative” means that something builds on itself. which example best shows how scientific knowledge is cumulative?
a) watson and crick worked together to come up with the model of dna.
b) kepler based his laws of planetary motions off of newton’s law of gravity.
c) hardy and weinberg independently came up with a population equation.
d) darwin and his grandfather both worked on the ideas of survivability.

The correct answer is B.  

Explanation:

"Cumulative" means that something builds on itself. Like one law is formulated from using the result of the other.

Newton's law of gravity had come after that Kepler's laws was formulated.

The law of gravity is more fundamental than Kepler's laws.

Newton formulated his famous law of gravitation between the earth and the moon and also between the Sun and the planet.

After that Kepler's laws came. He gave the law of orbit in which he said that the planet revolves the Sun in an eliiptical orbit. And the other two laws were also given by him.  In this way Kepler's law was formulated by using the law of gravity.

Therefore, Kepler based his laws of planetary motions off of Newton’s law of gravity is the best example to show how scientific knowledge is cumulative.