Question

Why are the Himalaya called the young fold mountain​

Answer 1

They are young because they are being formed from the collision between India and Asia, a collision which began only about 30 million years ago and is still going on. They are folded mountains because they are formed by folding of the rocks along the edges of both continents from the force, pressure, and heat of the collision. We'll also find low-angle thrust faults at depth in abundance, but they qualify as folded mountains, like the Appalachians or the Alps.