1. Among the 8 vertices and the center of a cube, a total of 9 points, the number of sets of four coplanar points is ( ).
(A) 28
(B) 32
(C) 36
(D) 40
1.C.
A cube has 6 sides forming 6 different sets of coplanar four points. Additionally, a cube has 6 diagonal sections, each of which, together with the center 0 of the cube, can produce 5 different sets of coplanar four points. Thus, this results in $6 \times 5+6=36$ different sets of coplanar four points.