With reference to the religious history of India, consider the following statements: 1. Sthaviravadins belong to Mahayana Buddhism. 2. Lokottaravadin sect was an offshoot of Mahasanghika sect of Buddhism. 3. The deification of Buddha by Mahasanghikas fostered the Mahayana Buddhism. Which of the statements given above is/are correct?

Let's analyze each statement regarding the religious history of India, specifically Buddhism:

1. Sthaviravadins belong to Mahayana Buddhism. This statement is incorrect. Sthaviravada (meaning 'Doctrine of the Elders') is the precursor to what is known today as Theravada Buddhism. It is an older, more conservative school that claims to adhere more closely to the original teachings of Buddha. Mahayana Buddhism (meaning 'Great Vehicle') emerged later and represents a different path to enlightenment, focusing on the Bodhisattva ideal and developing more elaborate cosmological concepts. Theravada and Mahayana are two distinct major branches of Buddhism, not sub-schools of each other.

2. Lokottaravadin sect was an offshoot of Mahasanghika sect of Buddhism. This statement is correct. The Mahasanghika ('Great Assembly') school was one of the earliest schismatic schools of Buddhism, emerging after the Second Buddhist Council. The Lokottaravada ('Supra-mundane Doctrine' or 'Transcendentalist') was indeed a prominent sub-school or offshoot of the Mahasanghika tradition. They held the view that Buddha was 'Lokottara' or supra-mundane, i.e., transcendental and beyond the worldly realm, differing from the more human portrayal in early Buddhism.

3. The deification of Buddha by Mahasanghikas fostered the Mahayana Buddhism. This statement is correct. The Mahasanghikas were instrumental in the doctrinal developments that paved the way for Mahayana Buddhism. Their emphasis on the 'Lokottara' nature of Buddha (viewing him as a divine or semi-divine figure rather than just a human teacher) and their early ideas about Bodhisattvas (enlightened beings who delay their own nirvana to help others) were crucial elements that evolved into the core tenets of Mahayana Buddhism.

Therefore, statements 2 and 3 are correct.