How are scientists investigating the evolution of language?

A) by studying behavior in nonhuman relatives
B) by studying the genetics of language
C) by studying the evolution of the brain
D) all of the above

Scientists investigate the evolution of language through a variety of methods, including studying behavior in nonhuman relatives to understand the origins and development of communicative behaviors, examining the genetics of language to identify genes that might influence language ability, and researching the evolution of the brain to understand how changes in brain structure and function could have supported the emergence and development of language capabilities.