As in chimpanzees, captive bottlenose dolphins have been taught American Sign Language. Th

As in chimpanzees, captive bottlenose dolphins have been taught American Sign Language. These dolphins have learned to communicate with trainers who use sign language to ask simple questions. Dolphins answer back by pushing a "yes" or "no" paddle. They have even been known to give spontaneous responses not taught by the trainers. Evidence also indicates that these dolphins can distinguish between commands that differ from each other only by their word order, a truly remarkable achievement. Nevertheless, dolphins do not seem to have a real language like ours. Unlike humans, dolphins probably cannot convey very complex messages.

The word "insights" in the passage is closest in meaning to

A．examples

B．understanding

C．directions

D．discussion

请帮忙给出正确答案和分析，谢谢！