History · Ancient Indian Religions

Consider the following statements regarding Buddhism: 1. The Four Noble Truths form the central doctrine of Buddhism. 2. The concept of 'Anatta' (Anatman) in Buddhism denies the existence of a permanent, unchanging soul. 3. Mahayana Buddhism introduced the prominent concept of the Bodhisattva. 4. The 'Milindapanha' is a Pali text that records a dialogue between the Indo-Greek king Menander I and the monk Nagasena. Which of the statements given above are correct?