Concept:This question tests the concept of competitive supply, where two commodities compete for the same productive resources.
Explanation:When the price of commodity X rises, producers find X more profitable.
So producers shift resources, such as land, labour, and capital, from producing Y to producing X.
As a result, the supply of X increases while the supply of Y falls.
This shows that commodities X and Y are produced under competitive conditions because they use the same limited resources.
These commodities are, therefore, competitive goods or goods in competitive supply.
Answer:A. competitive goods