The wide treeless grassy plain in South America are called

The correct answer is (b), Pampas.

The Pampas are a vast grassland that covers parts of Argentina, Uruguay, and southern Brazil. They are home to a variety of wildlife, including deer, armadillos, and rheas. The Pampas are also an important agricultural region, where crops such as wheat, corn, and soybeans are grown.

The other options are incorrect.

(a) Selvas are tropical rainforests that are found in South America.
(c) Prairies are grasslands that are found in North America.
(d) Steppes are grasslands that are found in Europe, Asia, and North America.