What colour of ppt.is formed when ${\mathrm{KHCO}}_3$ reacts with excess${\mathrm{AgNO}}_3$ followed by boiling?

When ${\mathrm{KHCO}}_3$ interacts excessively with excess ${\mathrm{AgNO}}_3$, followed by boiling, brown colour of ppt. is produced.

${\mathrm{AgNO}}_3+{\mathrm{KHCO}}_3\to {\mathrm{AgHCO}}_3+{\mathrm{KNO}}_3$

${\mathrm{AgHCO}}_3$ is a brown precipitate

Hence correct option is C