What is the best way to prove my maintenance funds?

On the home office website under supporting documents for maintenance (funds) it states the documents are:

-Personal bank or building society statements covering the three-month period immediately before the application

-Building society passbook covering the previous three-month period

-Letter from bank confirming funds and that they have been in bank for at least three months

-Letter from financial institution regulated by the Financial Services Authority (FSA) or the home regulator confirming funds


Does this mean I have to provide all of the above or just either one?