A triangle can have a maximum of one non-acute angle. This is best represented by option A.
In a triangle, all angles add to 180°. Another name for angles that add to 180° is supplementary angles. If we have 3 acute angles (all of which are less than 90°), we physically cannot add them all up to 180° because the sum of three angles less than 90 degrees sums up to a value less than 180 degrees. A triangle can have a maximum of one right or obtuse angle, as a right angle is equal to 90° while an obtuse angle is greater than 90° but less than 180°. Using two acute angles (equal to 45°) will result in the addition of a right angle to the measurements, while using two acute angles less than 45° will result in the addition of an obtuse angle.
Therefore, a triangle can have a maximum of A. one acute angle.