Answer:
Option B
Step-by-step explanation:
Proof planning : It is a method or technique for guiding the search for a proof in automated theorem proving.
Process of proof planing:
1. Constructs the proof plan for a proof.
2. Then uses it to guide the construction of the proof itself.
In the plan of a proof, sometimes you should use the plan that was used on previous theorems.
Therefore, the correct option is B.