I have sold some bitcoins with my paypal account, and now Paypal is asking me for clarifications for the bitcoin transactions.
What should I tell them ? I guess it's not allowed to deal with bitcoins ? What will they do if I tell them I sold bitcoins ? Can they refuse to give me my money ?
I doubt they are going to release your account now.
Any kind of currency exchange is against PayPal's Acceptable Use Policy.
Check point # 3(h) here:
https://www.paypal.com/uk/webapps/mpp/ua/acceptableuse-full