The Key to Understanding Francis Bacon's Thoughts Is His Claims

The key to understanding Francis Bacon's thoughts is his claims that:

A) one should use deductive thinking to prove metaphysical theories.
B) one should use inductive thinking to acquire knowledge and that knowledge should be useful.
C) to acquire real knowledge, one must start with certain definitions, and true knowledge must be carefully separated from useful knowledge.
D) mathematical knowledge, built upon both inductive and deductive reasoning, was essential to understand nature.