Take a look at the item again:
Mrs. Neal loves chocolate cake. (A)
But couldn't accept the slice that her student Michael
offered (B)
because she knew that it was a bribe
(C) for a better grade
on his midterm essay.
You wanted to do this:
Mrs. Neal loves chocolate cake. But couldn't accept the slice that her student
Michael offered. Because she knew that it
was a bribe for a better grade on his midterm essay.
A period after offered makes a fragment. Because she knew ... is a subordinate clause which cannot stand alone as a complete sentence.
You might want to review the rules.
Go back to the sentence to try again.