Answer:
Option B
Step-by-step explanation:
All equilateral triangles are "acute triangles" or option B. Acute triangles have degrees that are less than the degree of a right triangle which is 90 degrees. In this case all equilateral triangles have the sum of 60 degrees, which is less than the degree of a right triangle which means it is indeed a acute angle. It's not option D because obtuse triangles are triangles with angles that are more than 90 degrees, it's also not option C because each side of a scalene triangle is of different length in terms of degrees.
Hope this helps.