In Store Manager > Website > Checkout and Credit Cards you can control what credit cards are accepted at checkout.
Credit Cards Accepted
Visa and Mastercard will be checked by default. Be sure to check any additional cards you accept.
We really recommend that you require the CVV2 at checkout. If you are using authorize.net, this is a requirement.
Note that even though we collect the CVV2 at checkout and authorize.net uses it during the pre-authorization, we cannot display it within an order. No one at Modern Retail has access to that data.