Suppose That a Worker in Country a Can Make Either

Suppose that a worker in Country A can make either 10 iPhones or 5 iPads each year. Country A has 100 workers. Suppose a worker in Country B can make either 2 iPhones or 10 iPads each year. Country B has 200 workers. Country A would be using resources efficiently if it was producing:

A) (500 iPhones, 100 iPads) .
B) (500 iPhones, 150 iPads) .
C) (500 iPhones, 200 iPads) .
D) (500 iPhones, 250 iPads) .