Which finding, if true, would most directly support Martinez and coll… | Verbal SAT Question

The bird species Piculus flavigula (the yellow-throated woodpecker) shares some territory in French Guiana with Thamnomanes caesius (the cinereous antshrike), which emits a loud alarm call when it detects predators. Biologist Ari Martinez and colleagues recorded T. caesius alarm calls and played them in the vicinity of wild P. flavigula. Finding that the birds often froze in place or scattered into vegetation upon hearing the calls, they concluded that P. flavigula associates T. caesius alarm calls with danger.

Which finding, if true, would most directly support Martinez and colleagues’ conclusion?

Martinez and colleagues played alarm calls from different T. caesius individuals and observed no significant variation in the responses of P. flavigula.

In some instances, P. flavigula froze in place or scattered into vegetation when Martinez and colleagues approached but before they began playing sounds.

When Martinez and colleagues played control sounds of random noise in the vicinity of P. flavigula, the birds displayed no reaction.

Other bird species than P. flavigula also showed a tendency to freeze in place or scatter into vegetation when Martinez and colleagues played T. caesius alarm calls.