What is the relationship between GMC and General Motors in the context of the input sentence. Choose an answer from: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

Fold in the Silverado's upscale twin, the GMC Sierra, and General Motors ( NYSE:GM ) sold more full-size pickups in the first half of 2015 than mighty Ford ( NYSE:F ) .

Answer: parent_organization