Look at the ANSWERS for Clues. We see two Commas inserted and which, whom, and who. Underline your clues. Which pronoun best describes company? A company is not a whom or a who – that’s for people, so we could ELIMINATE H & J. That leaves should there be a Comma after “company?”
Answer F – No change. KEEP F because it is a company that had donated… makes sense. When you use the word that with a clause no commas are needed. This is a restrictive clause. You need the information to identify and give more information about the company.
Answer G ELIMINATE G because we see a non-restrictive clause. The information is extra and can be removed. Non-restrictive “Which” clauses have commas at the beginning and end when they are in the middle of a sentence. There is no comma after project, so this cannot be a “which” clause.
The Correct Answer is