Final answer:
The correct correction to the sentence is B. Karen, a shift manager, will lead our new staff orientation, on Monday, December 8th at 9 am.
Step-by-step explanation:
The correct correction to the sentence is:
B. Karen, a shift manager, will lead our new staff orientation, on Monday, December 8th at 9 am.
In this sentence, the correction is the addition of commas to set off the phrase 'a shift manager.' Commas are used to separate additional information or nonessential phrases from the rest of the sentence. In this case, 'a shift manager' provides additional information about Karen, so it should be enclosed by commas.