Option a is the correct answer. Ramanujacharya, the founder of Vishishtadvaita Vedanta, accused Adi Shankara of being a Prachanna Bauddha, that is, a "crypto-Buddhist". He claimed that Shankara's philosophy of Advaita Vedanta was actually a disguised form of Buddhism, and that it contradicted the teachings of the Vedas and the Upanishads. Ramanujacharya argued that Shankara's doctrine of non-dualism (advaita) was similar to the Buddhist doctrine of emptiness (sunyata), and that his concept of maya (illusion) was similar to the Buddhist concept of avidya (ignorance). Ramanujacharya also criticized Shankara's rejection of the reality and diversity of the world, and his identification of the self (atman) with the ultimate reality (Brahman). Important Tips Ramanujacharya proposed a different interpretation of Vedanta, which he called Vishishtadvaita, meaning qualified non-dualism. He maintained that Brahman is the supreme reality, but that it has attributes (vishishta) and modes (prakara). He also affirmed the reality and diversity of the world, and the existence of individual souls (jivas) who are dependent on Brahman. He advocated for a path of devotion (bhakti) and surrender (prapatti) to Brahman as the means of attaining liberation (moksha).