Credit card:
The credit will be credited back to the debited credit card account. You can view the chargeback on your current or next credit card statement.
PayPal:
The credit will be posted back to your used PayPal account. With PayPal, you can decide whether the amount is deposited on your PayPal account or booked back from there to your bank account.
Prepayment:
Credit will be issued to your bank account.