The displacement of a particle in a string carrying a travelling wave is represented by the equation $\mathrm{y}=\mathrm{A} \sin \left(\mathrm{Kx}-\omega t+\mathrm{\varphi }\right)$. At t = 0, The particle at x = 0 is at half of amplitude and is moving in upward direction. Then value of $\mathrm{\varphi }$ is

• A

  60^o

• B

  120^o

• C

  30^o

• D

  300^o