The tax on a commodity is diminished by 20% but its consumption is increased by 10%. Find the decrease percent in the revenue derived from it?	Select.
A) 20 %	B) 19 %	C) 15 %	D) 12 %	E) 24 %

Rationale: "answer : option d 100 * 100 = 10000 80 * 110 = 8800 10000 - - - - - - - 1200 100 - - - - - - - ? = 12 %"
Answer: D