What nickname was used for experienced gold miners?

A Desperados
B Greenhorns
C Sourdoughs

Gold mining often meant a tough life where food could be scarce. A reliable source of it was sourdough bread. Miners would keep a pouch of sourdough starter on their body to keep it warm. Thus, experienced miners were often called sourdoughs. In Yukon that meant you had spent at least one full winter in the cold, inhospitable territory.

The correct answer is Sourdoughs.