Benjamin Whorf and Edward Sapir's work studying the Hopi, a Native American group in the southwestern United States, showed that the Hopi language had no verbs to distinguish between past and present. Whorf continued from this observation to make what claim about the relationship between language and thought:

a. language creates/informs different ways of thinking
b. thought and language are entirely unrelated
c. there is a universal language that we can all understand
d. language is genetically inherited