According to thiong'o, what must colonizers do in order to control a colonized people mentally?
a. they must show the colonized that people what it means to live in a civilized manner.
b. they have to destroy the colonized people's culture, including their literature and language.
c. they have to present the colonized people with religious reasons why they need to change.
d. they must bring gifts and money in exchange for using the resources of the colonized people's land.

B. They have to destroy the colonized people's culture, including their literature and language.

Explanation:

This is the most effective way to control the colonized people mentally, according to Thiong'o. This is because culture, including language and literature, provides a common identity between the colonized people. A common identity, in turn, can provide a sense of unity, and people are more likely to unite in order to protect the culture that they feel is uniquely theirs.

the answer is culture