$A$ galvanometer of resistance $20 \Omega$ gives a deflection of $5$ divisions when $1 \text{ mA}$ current flows through it. The galvanometer scale has $50$ divisions. To convert the galvanometer into a voltmeter of range $25 \text{ V}$,we should connect a resistance of

• A
  $1240 \Omega$ in series.
• B
  $2480 \Omega$ in series.
• C
  $2480 \Omega$ in parallel.
• D
  $20 \Omega$ in parallel.