Take a look at the item again:
Because he had eaten a stack of twelve pancakes,
(A) Emanuel heard his
stomach begin to rumble (B)
as it processed the food. (C)
Gurgling loudly to protest the huge meal.
You wanted to to this:
Because he had eaten a stack of twelve pancakes.
Emanuel heard his stomach begin to rumble as it processed the food.
Gurgling loudly to protest the huge meal.
Adding a period after pancakes will make Because he had eaten a stack of twelve pancakes a fragment.
You might want to review the rules.
Go back to the sentence to try again.