Which triangle is not possible to construct?

Question

A a right isosceles triangle
B an acute equilateral triangle
C an obtuse scalene triangle
D a right equilateral triangle

Would it be A

Answer 1

An equilateral triangle has three 60 degree angles.
That leaves no corner for a 90 degree angle.

Answer 2

so would it be B

Answer 3

im so confused

Answer 4

But im pretty sure it cant be B tho because making an equilateral is possible with a right angle right?

Answer 5

NO,
To make D you need three 60 degree angles and a 90 degree angle.
Try to draw that.