Concept:The earth acts as a large reservoir at zero potential. Connecting a charged conductor to the earth allows the conductor to become neutral by the flow of charges.
Explanation:A positively charged conductor has a shortage of electrons.
When it is connected to the earth, the excess positive charge attracts electrons from the earth.
These electrons flow from the earth into the conductor.
This flow neutralises the positive charge and brings the conductor to zero potential.
The only particles that move physically in this process are electrons, not protons or ions.
Protons are firmly fixed inside the nucleus and cannot move freely in a conductor.
Answer:Electrons (Option A) flow to the positively charged conductor.