A demand function for air conditioners is given by:
= 10,000－2 + 0. 0004 income + 30 －4 . At current average prices, an air conditioner costs 5,000 yen, a fan costs 200 yen, and electricity costs 1,000 yen. Average income is 4,000,000 yen. The income elasticity of demand for air conditioners is closest to:

A.0.0004.

B.0.444.

C.40,000.