What advantage does a business letter have over an e-mail?
because it takes longer to write and send, it allows “cool down” time.
a business letter is faster and more effective than e-mail.
most companies won’t accept e-mail complaints and only respond to letters.
it is better to visit the company in person than to write an e-mail or letter.

The answer is A: Because it takes longer to write and send, it allows “cool down" time. This is because the time it akens them to acknowledge the letter and mail another one to you it would've given you time to think about the situation and blow some steam off. Hope i helped (:

i cannot see any of the options                                                                        

i would need the available options to be listed to give you an answer.