Which one of the following shows optical activity

• A

  $HO - \mathop {\mathop {\mathop {\mathop C\limits^| }\limits^H }\limits_| }\limits_H  - COOH$

• B

  $C{H_3} - \mathop {\mathop {\mathop {\mathop C\limits^| }\limits^H }\limits_| }\limits_{Cl}  - COOH$

• C

  $C{H_3} - \mathop {\mathop {\mathop {\mathop {C - \,}\limits^{|\,\,\,\,\,} }\limits^{C{H_3}} }\limits_{|\,\,\,\,\,\,} }\limits_{OH\,\,} COOH$

• D

  $C{H_3} - \mathop {\mathop {\mathop {\mathop {C - \,}\limits^{|\,\,\,\,\,\,} }\limits^{C{H_3}} }\limits_{|\,\,\,\,\,\,} }\limits_{Cl\,\,\,} COOH$