Which of the Following Statements About Nonhuman Primates' Ability to Learn

Which of the following statements about nonhuman primates' ability to learn language is true?

A) Nonhuman primates have essentially no ability to learn how to use words to communicate.
B) Nonhuman primates can learn vocabulary and simple sentence structure, but the communicative system they can acquire is not generally considered to be a language.
C) Nonhuman primates naturally use language to communicate with other members of their species,although their languages are not as complex as humanlanguages.
D) Nonhuman primates do not have the vocal apparatus for producing speech, but when they are taught a sign language, they are able to learn a complex language.