When an ant bites a human, what does it inject into the human skin ?

When an ant bites (particularly red or fire ants), it injects formic acid (HCOOH) into the skin through its sting.
This acid causes the burning sensation, irritation, and redness commonly experienced after an ant bite.

Formic acid is named after the Latin word “formica”, meaning ant, because it was first isolated from ants.

The chemical formula of formic acid is HCOOH.

To relieve an ant bite, applying a mild base like baking soda paste (NaHCO₃) or calamine lotion helps neutralize the acid and reduce irritation.

Final Answer: (D) Formic acid