who can help me....i canot use my parents cc do do the verification ....
they dunot accpet it..duno why..
btw the webpage dun have the monthly prepaid card option but visa, master, american express.......

Are you creating a new account? If so, you don't have to worry. It will only be used for verification purpose and your parents CC will not be billed as long as you cancelled your account before the one-month free period ends. I would suggest you do it asap after you created your account in case you forget later. You will still have access to your account for the next 30 days and you can add your gamecard after that.

its not neccesary to use the guess pass to play the 10-days trial.
get this link, https://signup.worldofwarcraft.com/trial/10dayfreetrial.htm
no nid credit card to register whereas using guess pass requires credit card verification to do so.

Would there still be a one-month free period after the upgrade? If its so, this will definitely be the better option.

Yes, every purchase of WoW:Classic will be given a one-month free period, including upgrade from 10-days trial account.