Answer:
A. Stop payment on the first check; then write a second one.
Step-by-step explanation:
There are certain rules and procedures in banking system. If any check written is lost, then firstly the check shall be made invalid the one which is lost.
To make it invalid, stop payment can be done. Stop payment basically converts the check into a mere paper, with no validation, even if such check is presented no payment is made against it.
Further by issuing check you create a liability that you owe some money as against the party in consideration on check.
Therefore, after stop payment a new check shall be issued.