Explanation:

- Gandhiji regarded Gopal Krishna Gokhale as his political guru.

- Option 1: Bal Gangadhar Tilak

- Leading figure in Indian National Movement.

- Not chosen by Gandhi as his mentor.

- Option 2: Pherozeshah Mehta

- Prominent lawyer and politician.

- No evidence he mentored Gandhi.

- Option 3: Gopal Krishna Gokhale

- Social reformer and senior Congress leader.

- Gandhiji openly called him his "political guru" for his moderate views and guidance.

- Option 4: Dadabhai Naoroji

- Early nationalist leader, known as "Grand Old Man of India."

- Influential for Gandhi but not specifically as his guru.