Question

1. choose the best answer. these mountains form the southern boundary of the central siberian plateau. caucasus kamchatkas baikals urals

Explanation:

The Caucasus Mountains are in a different region far from the Central - Siberian Plateau. The Kamchatkas are a peninsula in the far - east of Russia, not related to the southern boundary of the Central Siberian Plateau. The Urals form a different boundary (Europe - Asia boundary, not related to the Central Siberian Plateau). The Sayan Mountains (not listed here but the correct ones in fact) are close to Lake Baikal, and among the given options, the Baikals can be considered in the general vicinity of the southern part of the Central Siberian Plateau region.

Answer:

C. Baikals