Answer:
A. Right angled Triangle
Explanation:
The length and the width are not equal so we cannot have equilateral triangles,
An acute triangle is a triangle with three acute angles ( less than 90°) and since we have an angle that is 90° then the triangles are not acute.
An obtuse-angled triangle is a triangle in which one of the interior angles measures more than 90° degrees, which is NOT the case in our situation.
Therefore we have a right angled triangle since one angle=90°