If two angles of a triangle measure \[45{}^\circ \] and \[60{}^\circ ,\]then which of the following angle cannot be the measure of one of the exterior angles of the triangle?

• A.  \[105{}^\circ \]                        
• B.  \[120{}^\circ \]          
• C.  \[140{}^\circ \]             
• D.  \[135{}^\circ \]