Please help as quickly as possible.

D

Step-by-step explanation:

take a calculator and try a few points.

I used x = 10.3 and x = 22.

and only D is really getting close to 0.4 and 3.5 as functional results.

hello :

by applying the distributive property :

6 × 4.3 = 6 × ( 4 + 0.3 )

            =   (6 ×   4) + (6 ×   0.3)

            = 24 + 1.8

6 × 4.3 = 25.8

the answer is 21%.