The angle between the two vectors \[\overrightarrow{A}=5\hat{i}+5\hat{j}\] and \[\overrightarrow{B}=5\hat{i}-5\hat{j}\]will be [CPMT 2000]

• A.                 Zero      
• B.                 \[45{}^\circ \]
• C.                 \[90{}^\circ \]   
• D.                 \[180{}^\circ \]