If $P=\{x:sinx-cosx=\sqrt2 cosx\}$ and $Q=\{x:sinx+cosx=\sqrt 2 sinx\}$ then which of the following is true ?

Question

(A) $P\subset Q$

(B) $Q-P\neq \phi$

(C) $Q\subset P$

(D) $P=Q$