Which one of the following functions is NOT continuous at (0,0)? O f (x, y) = cos(2 + y? ) - 1 f (0, 0) - 0 ONone of these. O ry2 f ( x, y) = 12 4 72 : f (0, 0) - 0 O f(x, y) = x +y + 3, f(0, 0) -3 O f ( x, y ) = sin(2 2 + y2 ) 2 2 + 32 , f(0, 0) - 0