The length of AB is 2√2, and the area of triangle ABC is 2.

Then that distance from point c to straight line AB is √2,

The AB equation is y=-x+2,

The linear equation of the distance line AB√2 is y=-x+4 or y=-x,

The intersection of straight lines y=-x+4 or y=-x and y = x 2 is point c,

The straight lines y=-x+4 or y=-x and Y = x 2 have four intersections.

So choose a.