When the price of a t-shirt is $9, the quantity supplied is 9,500. When the price of a t-shirt is $11, the quantity supplied is 10,500. At the price of $10 a t-shirt, the Select one: A. supply of t-shirts is unit elastic. B. demand for t-shirts is elastic. C. supply of t-shirts is perfectly inelastic. O D. supply of t-shirts is elastic. E. supply of t-shirts is inelastic.