$A$ bottle containing $C_6H_5I$ and $C_6H_5CH_2I$ has lost its label. To identify them,samples $A$ and $B$ are taken in separate test tubes and boiled with $NaOH$ solution. Finally,the solution in each test tube is acidified with dilute $HNO_3$ and then a few drops of $AgNO_3$ solution are added. Substance $B$ gives a yellow precipitate. Which statement is correct for this process?

• A
  $A = C_6H_5I$
• B
  $A = C_6H_5CH_2I$
• C
  $B = C_6H_5I$
• D
  Addition of $HNO_3$ is unnecessary