Income Elasticity Question - Check My Answer!?

Question

Here's the Question: http://tinypic.com/view.php?pic=i2twyw&s=4

My Thoughts: I'm being swayed by different views here, but I need a clarification. Does a decreasing income causes something to become more elastic - or an inferior good? So, will B (or X) be the answer here or is it something else?

Answer 1

Elasticity = ΔQ% / ΔIncome%

Since ΔIncome% is negative (decrease in income) but ΔQ% is positive (quantity increasing) - so resulting elasticity should be negative number which is option "C. Z" in your case.