The correct answers are
A. The Jewish traveler Benjamin of Tudela visited India in the 12th century and reported finding a community of about 1000 Jews, “all of them black.” 100 years later, explorer Marco Polo traveled to the same area and described a thriving Jewish community there.
and
B. Cochin was a major center of the Jewish population in India, but now, only about 26 Jews remain in Cochin (approximately 8000 Cochin Jews live in Israel). One Cochin Jew, living in the Mattancherry section, was interviewed last year and said that there were only 6 members of the community left, but that was because she ignored the 20 “downtown” Jews in the Malabari area, with whom her group doesn’t speak. A Malabari Jew who was also interviewed said that “Those Jews [in Mattancherry] are idiots.”
and
C. One of the oldest Jewish communities in India is the Bene Israel, who live primarily in Mumbai and western India. They claim to be descendants of Jews who left the Galilee in the 2nd century BCE to escape persecution. They also claim to be descendants of Aaron, and DNA tests in 2002 confirmed their shared heredity with the Kohanim.
and
D. The Bene Menashe Jewish community of India resides in the northeast of the country. Claiming descent from the Biblical tribe of Menashe, they converted to Christianity in the 19th century, but many began practicing Judaism again after one of their leaders dreamed that God said he should return his people to their pre-Christian religion. Many have since emigrated to Israel.