Step 1: Context.
In the story "Gillu," Mahadevi Verma used Penicillin to treat wounds.
Step 2: Option Analysis.
(A) Penicillin: Correct.
(B) Soframycin: Incorrect.
(C) Vaseline: Incorrect.
(D) Gel: Incorrect.
Step 3: Conclusion.
Correct answer is (A) Penicillin.