Presence of five hydroxyl groups in glucose is indicated by its reaction with

• A

  $\mathrm{HCN}$

• B

  ${\left({\mathrm{CH}}_3\mathrm{CO}\right)}_2\mathrm{O}/{\mathrm{CH}}_3\mathrm{COOH}$

• C

  ${\mathrm{NH}}_2\mathrm{OH}$

• D

  $\mathrm{conc}. {\mathrm{HNO}}_3$