The potential difference V and the current i flowing through an instrument in an AC circuit of frequency/are given by $\mathrm{V}=5\cos \left(\mathrm{\omega t}\right)\text{ volts }$ and $\mathrm{I}=2\sin \left(\mathrm{\omega t}\right)$ amperes (where $\mathrm{\omega }=2 \mathrm{\pi f}\text{ ). }$ The power dissipated in the instrument is

• A

  Zero

• B

  10 W

• C

  5 W

• D

  2.5 W