These men are still are an integral part of the ranching areas of Argentina, Uruguay and Brazil. a) Asadas b) Mestizos c) Pantanals d) Gauchos

d) Gauchos are still are an integral part of the ranching areas of Argentina, Uruguay, and Brazil.

Explanation:

Gauchos are men in the above-mentioned countries who tend the cattle. They normally ride on horses to tend to a herd of cattle in farms and ranches. The name Gauchos originates from Quechua huachu which means vagabond or orphans. The herdsmen adopted the name during the Spanish colonial era.

They spent much time in the wilderness tracking lost cattle; provided protection to the animals and owners during battles; and sometimes provided military services too. They were hardly home due to their nomadic lifestyle therefore, they didn't play a big role in raising children. Growing up sons also became gauchos.

D. Gauchos is the answer.