A. You have two inequalities:
If you multiply the first inequality by positive number 4 (multiplying inequality by positive number doesn't change the inequality sign), then you get the inequality
[tex]4\cdot \dfrac{n}{4}<4\cdot 5,\\ \\n<20.[/tex]
B. You have two inequalities:
If you multiply the first inequality by negative number -4 (multiplying inequality by negative number changes the inequality sign), then you get the inequality
[tex]-4\cdot \left(-\dfrac{n}{4}\right)>-4\cdot 5,\\ \\n>-20.[/tex]
Answer: option D.