The angle between the two vectors \[\vec{A}=3\hat{i}+4\hat{j}+5\hat{k}\] and \[\vec{B}=3\hat{i}+4\hat{j}-5\hat{k}\] will be [Pb. CET 2001]

• A.            \[\text{9}0{}^\circ \]
• B.            \[0{}^\circ \]
• C. \[\text{6}0{}^\circ \]      
• D.            \[\text{45}{}^\circ \]