Answer:
b. A being that is explained by nothing.
Explanation:
The Principle of Sufficient Reason which was developed by Gottfried Wilhelm Leibniz, a 17th century philosopher, establishes the idea that everything has a reason and cause.
This principle propagates that 'for every fact or action, there must be enough reasons as to why it is a fact or has taken place.' It does not believe in the possibility of nothingness or explainable phenomena.
So the idea "A being that is explained by nothing." is supposedly eliminated when we apply the Principle of Sufficient Reason.