Concept:
- Use the most distinctive clue first, then check whether the remaining clues fit the same person.
- Vedantic theory is more specific than the general social-reform activities shared by several nineteenth-century leaders.
Step 1: Use the Vedanta clue.
Swami Vivekananda is closely identified with Neo-Vedanta and Practical Vedanta. He presented Vedantic ideas in a modern form and linked spirituality with service to humanity.
Step 2: Check the social-reform clues.
He criticised harmful customs, opposed child marriage, supported social uplift, and argued for reform within Hindu society. These clues agree with the identification.
Step 3: Eliminate the alternatives.
Jyotiba Phule, M. G. Ranade, and Gopal Hari Deshmukh were major reformers, but Vedantic theory is not their defining intellectual association.
Final Answer: Swami Vivekananda, option B.