Answer:
Option D. x = 1
Explanation:
If the two triangles Δ ABC and ΔDEC are similar then there corresponding sides will be in the same ratio.
Now using this theorem in these triangles

Now it has been given
AB = (4x - 1)
BC = 4
EC = 4
DE = x + 2
By putting these values in the formula

We cross multiply on both the sides
(4x - 1) = (x + 2)
4x - x = 1 + 2
3x = 3
x = 1
Option D. x = 1 is the answer.