การอ่าน TOEFL

❓ คำถาม According to the passage, what was a major limitation of earlier research on animal cognition?

A. A. It relied too heavily on laboratory experiments rather than natural observations.
B. B. It focused predominantly on primates, thereby overlooking cognitive abilities in other animal groups.
C. C. It failed to recognize the importance of ecological pressures in shaping intelligence.
D. D. It overestimated the brain-to-body ratio of corvids compared to that of great apes.

B. It focused predominantly on primates, thereby overlooking cognitive abilities in other animal groups.