The Southernmost point of India is called :

Concept

A country’s extreme points — its northernmost, southernmost, easternmost, and westernmost locations — are the outermost points of its sovereign territory in each direction. These are measured over the entire territory, including any outlying islands, which can lie well beyond the mainland’s own extremities.

Application

For India, the southernmost point of the entire sovereign territory is Indira Point, on Great Nicobar Island in the Andaman & Nicobar Islands. It was named in 1985 in honour of Prime Minister Indira Gandhi, replacing its earlier name, Pygmalion Point. This is distinct from Kanniyakumari (Tamil Nadu), which is only the southernmost point of the Indian mainland — the Andaman & Nicobar Islands extend further south than the peninsula, which is exactly why the island point, not the mainland point, is India’s true southernmost extremity.

Cross-check: the other extreme points and places

• Indira Col Point lies in the Karakoram range near the Siachen Glacier in Ladakh — the country’s northern extremity, in the opposite direction from the one the question asks about.

• Kibithu Point lies in Anjaw district, Arunachal Pradesh, along the Lohit river valley near the India–Myanmar frontier — the country’s eastern extremity, again a different cardinal direction.

• Kavaratti is the administrative capital and largest town of the Union Territory of Lakshadweep, among the coral atolls of the Arabian Sea — an inhabited administrative centre, not one of the four cardinal extremity points at all.

Checking each of the four cardinal extremities against the option values confirms that only Indira Point marks India’s southern extremity, so it is the correct answer.