○=> Correct option :
[tex]\color{plum}\tt\bold{(A) \: acute , \: equilateral}[/tex]
○=> Steps to derive correct option :
▪︎In this triangle all angles are less than 90°. We know that angles of a triangle which are less than 90° in measure will be called acute angles. Thus, this triangle is an acute angle when we classify it by it's angles.
▪︎All sides of this triangle are equal. We know that when all sides of a triangle are equal, it is to be called an equilateral triangle. Thus, this triangle is an equilateral triangle when we classify it by it's sides.
Therefore, the correct option is (A) acute, equilateral
