I have an English course book that contains this question:
Fill in the blank
"The book is a set of techniques that systematically __ the learner for interaction with target language speakers".
(A) prepare (B) preparing (C) prepares (D) prepared."
The answer given in the book is A, but isn't C correct? I used Google and found this example "DNA technology is a powerful set of techniques that ALLOWS scientists to examine, change, and create new genetic material"