Answer:
3 units
Step-by-step explanation:
The computation of the length of DC is shown below:
As we can see from the attached figure that the DE is parallel to BC with the help of basic proportionality theorem
Now the equation is
[tex]\frac{AE}{EB} = \frac{AD}{DC}[/tex]
[tex]\frac{12}{4} = \frac{9}{DC}[/tex]
DC × 12 = 9 × 4
DC × 12 = 36
So, DC
= 36 ÷ 12
DC = 3 units
Hence, the correct option is b. which determines the length of DC
