An organic compound having a carbon attached to four different groups is optically active. But is it that opposite is also true? That is, do all optically active organic compounds have chiral carbons? Not necessarily. Presence or absence of chiral centre is not the sufficient criteria for optical activity. The ultimate criteria is presence or absence of either plane or centre of symmetry. Two compounds which are non superimposable mirror images of each other are called enantiomers. If a compound contains more than one chiral carbon, new words are required to describe the relationship between various stereisomers of the compound. Those words are diastereomers and mesomers.
Optically active compounds among the following is

Options

A. I and II
B. II and III
C. I and III
D. IV and V

Answer

C

Explanation