A triangle is formed by joining three points whose coordinates are integers. If the x-coordinate and the y-coordinate each have a value of 1, then the area of the triangle, in square units:
<spanclass=′latex−bold′>(A)</span>must be an integer<spanclass=′latex−bold′>(B)</span>may be irrational<spanclass=′latex−bold′>(C)</span>must be irrational<spanclass=′latex−bold′>(D)</span>must be rational<spanclass=′latex−bold′>(E)</span>will be an integer only if the triangle is equilateral.