The population of a town is 20000. It decreases annually at the rate of 20% p.a. What will be its population after 2 years?
Choose the correct choice from the following options.
A) 4300
B) 4500
C) 5120
D) 5230
E) 12800

Rationale: "20000 × 80 / 100 × 80 / 100 = 12800 answer : e"
Answer: E