Prove whether a finite group of orthogonal transformations in R2 is either cyclic or a dihedral group Dih_(2n). Which of the following options correctly describes this statement?

A) A finite group of orthogonal transformations in R2 is always cyclic.
B) A finite group of orthogonal transformations in R2 is always a dihedral group Dih_(2n).
C) A finite group of orthogonal transformations in R2 can be either cyclic or a dihedral group Dih_(2n).
D) A finite group of orthogonal transformations in R2 cannot be either cyclic or a dihedral group Dih_(2n).