Answer:
Awareness (C)
Step-by-step explanation:
D would be eliminated because that just doesn't fit the definition.
Biologist (A) is a person and they do have knowledge, but another word would fit better. Plus, biologist has a different definition.
B would be finding out something. You will have a knowledge of it after to discover it. Plus discovery has a different definition.
This means C is the answer
Hope this helps!