In the adjoining figure, line P || line Q and line M and N are transversals. As per information in figure, find \[m\angle a+m\angle b\].

• A. \[225{}^\circ \]                     
• B.           \[90{}^\circ \]
• C. \[180{}^\circ \]                     
• D.           \[170{}^\circ \]