Final answer:
India is called a "subcontinent" because it is a large area of land separated from the continent of Asia by the Himalayas and surrounded on three sides by water.
Step-by-step explanation:
The best explanation for calling India a "subcontinent" is that India is a large area of land that is separated from the continent of Asia by the Himalayas. India is attached to the continent of Asia but surrounded on three sides by water.
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