Answer:
Option B x=6 units
Explanation:
we know that
If two figures are similar, then the ratio of its corresponding sides is proportional and its corresponding angles are congruent
In this problem
Triangles ABC and DEF are similar
therefore
∠A≅∠D
∠B≅∠E
∠C≅∠F
and
AB/DE=BC/EF=AC/DF
Find the value of x
AB/DE=BC/EF
substitute the given values
x/3=16/8
x=3*16/8
x=6 units