Answer:
B. They have to destroy the colonized people's culture, including their literature and language.
Step-by-step 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.