In the following tests, there are () a. Someone hit the target or missed the target. B. In the plane rectangular coordinate system, from the abscissa and ordinate,

For a, the probability of someone hitting the target and missing the target is not equal, which is not a classical probability, and a is wrong;

There are countless points, b, abscissa and ordinate are integers, not classical probability, and b is wrong;

For c, it conforms to the definition of classical probability, which is classical probability, and c is correct;

For D, the probability of shooting is different from the probability of not shooting, which is not a classical probability, and D is wrong;

So choose C.