You question is too broad. It sounds like you are asking for a comprehensive answer which can only be obtained on a consultation with an immigration attorney, who actually saw that RFE from USCIS.
NYC EXPERIENCED IMMIGRATION ATTORNEYS www.myattorneyusa.com; email: firstname.lastname@example.org; Phone: (866) 456-8654; Fax: 212-964-0440; Cell: 212-202-0325. The information contained in this answer is provided for informational purposes only, and should not be construed as legal advice on any subject matter.
It is impossible to answer your question without looking at the evidence you have already submitted and knowing the details of your case. You should seek a consultation with an immigration attorney near where you live.
I agree with my colleagues. Your question is much too broad to be meaningfully answered in a general forum such as this one.
Behar Intl. Counsel 619.234.5962 Kindly be advised that the answer above is only general in nature cannot be construed as legal advice, given that not enough facts are known. It is your responsibility to retain a lawyer to analyze the facts specific to your particular situation in order to give you specific advice. Specific answers will require cognizance of all pertinent facts about your case. Any answers offered on Avvo are of a general nature only, and are not meant to create an attorney-client relationship.
USCIS details specifically what they want as evidence for each case. The RFE should be clear as to what they want. If you are unable to determine from the letter, you may want to hire an attorney.
Samuel Ouya Maina, Esq. 415.391.6612 email@example.com Law Offices of S. Ouya Maina, PC 332 Pine Street, Suite 707 San Francisco, CA 94104