Detailed Solution:

The correct answer is “Shak”.

In ancient Indian literature and mythology, castes or groups such as Gandharv, Yaksha, and Kinnar are often mentioned as mythical or semi-divine beings believed to inhabit the Himalayan and surrounding regions.

These groups are associated with pre-Vedic and tribal traditions of the Himalayan region and are considered part of the prehistoric cultural landscape.

The Shak (Shaka) were historical Central Asian tribes who migrated into India much later, during the early centuries CE (Common Era), and thus are not considered prehistoric in the context of the Himalayan region.