If $\overrightarrow{\mathrm{P}}.\overrightarrow{\mathrm{Q}}=\mathrm{PQ},\mathrm{then}\mathrm{the}\mathrm{angle}\mathrm{between}\overrightarrow{\mathrm{P}}\mathrm{and}\overrightarrow{\mathrm{Q}}$

• A

  $0^0$

• B

  ${30}^0$

• C

  ${45}^0$

• D

  ${60}^0$