The correct answer is: b) Austroasiatic
Khasi and Garo are two languages spoken in the Indian state of Meghalaya. They are both members of the Austroasiatic language family, which also includes Vietnamese, Khmer, and Mon. Austroasiatic languages are spoken by about 100 million people in Southeast Asia, India, and China.
Tibeto-Burman languages are spoken by about 400 million people in Tibet, China, India, Nepal, Bhutan, Myanmar, and Bangladesh. Indo-Aryan languages are spoken by about 2 billion people in India, Pakistan, Bangladesh, Nepal, Sri Lanka, Afghanistan, and the Maldives. Dravidian languages are spoken by about 250 million people in India, Sri Lanka, and Pakistan.
Khasi and Garo are tonal languages, which means that the pitch of a word can change its meaning. They are also agglutinative languages, which means that words are formed by adding suffixes to a root word.
Khasi is the official language of Meghalaya and is spoken by about 1.2 million people. Garo is spoken by about 500,000 people in Meghalaya and Assam.