The unit vectors along the mutually perpendicular x, y and z axes are î, ĵ and k̂ respectively. Consider the plane z = 0 and two vectors \(\vec a\;and\;\vec b\) on the plane such that \(\vec a \ne \alpha \vec b\) for any scalar α. A vector perpendicular to both \(\vec a\;and\;\vec b\) is

• A. k̂
• B. î - ĵ
• C. –ĵ
• D. î