Question

The compound(s) showing optical activity is/are

• A. Option a
• B. Option b
• C. Option c
• D. Option d

Hint:

Optical activity checklist:

• Four different groups on carbon \( \Rightarrow \) chiral
• Check for meso symmetry
• Multiple chiral centers \( \neq \) always optically active

Answer 1

The Correct Option is B

Concept: A compound is optically active if:

• It has at least one chiral center
• It has no internal plane of symmetry (no meso form)

Analyze each option: (A)
Central carbon has: \[ \text{COOH, NH}_2, H, H \] Two identical substituents (H, H) ⇒ achiral. Not optically active.
(B)
Central carbon attached to: \[ \text{COOH, OH, CH}_3, H \] All four substituents different ⇒ chiral center present. Optically active.
(C)
Structure resembles glyceraldehyde type: \[ \text{CHO, OH, CH}_2\text{OH, H} \] Four different groups around carbon ⇒ chiral. Optically active.
(D)
Contains two stereocenters but has an internal plane of symmetry (meso compound). Thus optically inactive.
Conclusion:
Optically active compounds: B and C.