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)