Answer: C) Any topic you choose for research must be manageable.
Step-by-step explanation:
In the English language, redundancy is the use of two or more words that have the same meaning. This term is used for the expressions in which the meaning of a modifier is already conveyed in the word it modifies. For example - early beginnings, or join together.
Sentence C is thus the only sentence with no redundancy. In sentence A, 'forever and ever' is an example of redundancy; in sentence B- 'p.m. in the afternoon'; in sentence D- 'apply for' and 'admission.'