options question

I received my options exercise form in the mail the other day and it states as at the 25th May I held X amount of options and to forward a cheque to cover the amount of shares @ 0.10 on the form. Since that date I have sold all MPOOA I held, now the question is can I still lodge this form with a cheque and buy the amount of shares quoted on the form even though I have sold out of MPOOA. I still hold plenty of heads. Please excuse my ignorance, this is the first time I have dealt with options.