Newton ovserved the action of the prism on white light and on red light because

Newton observed the action of a prism on white light and on red light. Because he did control the event, this investigation of light was a controlled experiment. Explanation: ... Many years before Newton, one had the idea that the white light gave rise to a colored beam when it crossed a prism of glass.

Explanation:

this allows people to make the best decision or pursue the best option. when alternatives are weighed using their advantages and disadvantages, the option whose disadvantages outweigh the advantages (based on a qualitative or quantitative analysis) are shunned while those whose advantages outweigh their disadvantages are pursued.