An individual goes to a casino two weekends every year. While there, he usually loses several thousand dollars gambling. In between casino visits, he neither gambles nor thinks much about gambling. The MOST accurate assessment of this behavior would be:

a. This behavior is not a gambling disorder.
b. This behavior may not be a gambling disorder because the person doesn't gamble often enough.
c. This behavior may not be a gambling disorder because the person doesn't lose enough money.
d. This behavior is a gambling disorder.