If you do use e-mail to send a complaint, it’s a good idea to keep a copy so you have a record of the communication cc the attorney general of your state so he or she can take action print out a copy and mail it to yourself so you have a file copy cc the owner of the company you are contacting so he or she is aware of the problem

The question is asking "If you do use e-mail to send a complaint, it’s a good idea to" and we have a number of options. Let's look at them. 1) keep a copy so you have a record of the communication - this is always a good idea! this is also the correct answer. It's always good to keep a copy so that you can prove what happened 2) CC the attorney general of your state so he or she can take action - that is too much and the attorney would likely not react, unless your case is very important 3) print out a copy and mail it to yourself so you have a file - this is not necessary, a digital copy is perfectly enough 4) copy CC the owner of the company you are contacting so he or she is aware of the problem - this is not always necessary - first you should try to solve the problem with the employees, and only then go to the owner.