Question

The compounds (I) and (II) are optically inactive because

• A. Both compounds have the plane of symmetry.
• B. Both compounds have the centre of symmetry.
• C. Compound (I) has the plane of symmetry, while compound (II) has the centre of symmetry.
• D. Both (a) and (c)

Answer 1

The correct option is D Both (a) and (c)

The molecule I and II both contain a plane of symmetry passing through the two vertex, perpendicular to the ring containing $COOH$ groups.
Apart from this, molecule I also has another plane of symmetry passing through mid-point of two sides and perpendicular to the ring in which the two $COOH$ groups look like mirror images of each other.


For molecule II, $COOH$ group present at equidistance at opposite direction. Hence, centre of symmetry is also present.

Hence, (d) is correct.