A isnt correct because radius goes from center of circle to any point on circle. Chord on the other hand connects 2 points on circle...
B is also false. Secant goes through circle while tangent only touches it in one point.
C is correct. Chord connects as said before 2 points on circle and in some cases it can connect 2 points in such way that it goes through center which is diameter.
D is not correct because chord doesnt have to pass trought center of circle in order to connect any 2 points on circle.
