Answer:
The answer shall be letter D, which is 5.
For the solution, let us use the method called "Decrease in Percentage".
First, let us subtract 100% from 75% in this question.
100% - 75% = 25%
Second, convert 25% into a decimal by moving its decimal place to the left twice and removing the percent sign.
25% -> 0.25
Lastly, multiply 20 by 0.25.
20 x 0.25 = 5
For the complete solution of the multiplication, it is on the picture shown.
