Which of the following linear transformations from R^3 to R^3 are invertible ?

A. Projection onto the z-axis

B. Rotation about the x-axis

C. Dilation by a factor of 3

D. Reflection in the origin

E. Trivial transformation (i.e. T(v)=0 for all v)

F. Identity transformation (i.e. T(v)=v for all v)