What is Visa Number?

I really appreciate any response about visa number. I was required to fill out a form, which requires to provide visa number. I don't know what number I should pick. I checked my visa page, there are 3 numbers there. one is a control number, at the upper-right corner. one is a 8-digit red number, at the lower-right part. last one is a very long number, at the bottom.

Thank you very much in advance. Merry Christmas to you all!