Answer:
C. proofread her work carefully, ask a coworker to look it over, and correct all mistakes
Explanation:
Since in the question it is mentioned that Karen just finished the typing for an important memo and wants to send to many persons involved the president of the company
So here karen should proofread her work carefully and if it involved any kind of mistake that it should be corrected so that it would not create a bad presentation to the many people
Hence, the correct option is C.
