According to Paul Sherman's (1977) work, why do male Belding's ground squirrels rarely produce the first alarm call when a predator is nearby?

A) Calls are costly, and the squirrels are surrounded by unrelated individuals.
B) Males cannot produce these high-pitched vocalizations as well as females can.
C) Males advertise to predators instead of producing alarm calls.
D) Males are not attacked by predators .
E) Males have poor vision and so do not see predators first.