The region of the siberian plain where low-growing, cold-resistant vegetation grows is known as:

The correct answer is - taiga.

Siberia is harsh place for any organism to survive in, and this is mainly because of the winter that lasts for most of the year, and there's very deep snows and temperatures as low as - 50 and - 60 °C. Because of this all the plants living here have adapted to the harsh conditions and a highly specialized species which form the vast taiga. The taiga is the largest forest in the world, but it is a forest where the trees are not very high, and the other plants are low as well, and they are not active for the biggest part of the year but are in a hibernation faze, which makes them grow very slowly, but also makes them much more resilient and able to survive.