Furthermore, as Detroit automakers continue to rely on full-size trucks and SUVs for a majority of their profits, it's a good sign for investors that GM's Chevy and GMC brands sold more than 86,000 pickups in July -- GM's best figure since July 2006.
Analyze the relationship between 'GMC' and 'Detroit' within the context of the input sentence.
Options: publisher, operator, manufacturer, headquarters location