The only anthropoid ape to be found in India is the

The correct answer is the white‑browed gibbon (Hoolock gibbon). Gibbons are lesser apes (anthropoids) rather than monkeys, and sources note that the Hoolock/white‑browed gibbon is the only ape recorded from India, occurring in the Northeast (Assam and adjoining areas) [2]. Book material explicitly states that the Rongoli (Hoolock) gibbon is the only ape found in India [1], and conservation summaries and regional primate guides likewise identify the Hoolock gibbon as the sole ape species in the Indian subcontinent, sometimes referred to as the white‑browed gibbon or hoolock gibbon in Assam [2].

Sources

1. [1] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 12: Animal Diversity of India > Do you know? > p. 192
2. [2] https://www.natureinfocus.in/environment/seven-of-india-s-primate-species-are-in-danger