In the following question, select the related word pair from the given alternatives.
Gun : Soldier :: ? : ?

The relationship in the given pair is Tool : Professional.
A gun is the primary tool used by a soldier.

Let us evaluate the options:

Pen : Carpenter: A carpenter uses a saw or planer, not a pen as their primary professional tool.

Plough : Surgeon: A surgeon uses a scalpel, not a plough.

Chisel : Sculptor: A chisel is the primary tool used by a sculptor to carve materials. This matches the logic perfectly.

Sword : Doctor: A doctor uses a stethoscope or scalpel, not a sword.

Therefore, the related word pair is Chisel : Sculptor.