Here's why:
* Quotation marks: The words "Great job" are a direct quote, so they need to be enclosed in quotation marks.
* Comma: Since the sentence is describing the action of shouting, we need a comma after "shouted" to separate the action from the quoted words.
* Exclamation point: The phrase "Great job" is an exclamation, so it needs an exclamation point at the end.