The reaction of an organic compound, like a hydrocarbon, as it burns in the presence of oxygen is called

combustion

Explanation: When a compound burns in the presence of oxygen the reaction is called a combustion. Like most organic substances, hydrocarbons are combustible. The general reaction is given below. Organic Compound + O 2 (g) ! CO 2 (g) + H 2 O(g) + Heat=Energy (1)

c is the answer because when something is left after something evaporates that shows the chemical change.