Question

During combustion ,a combustible substance combines with ________to produce heat and light. 
i) Argon
ii) Nitrogen
iii) Oxygen
iv) Hydrogen​

Answer 1

A chemical process in which a substance reacts with oxygen to give off heat is called combustion. The substances which undergo combustion are known as combustible substances. It may also be called a fuel.

Answer 2

Answer:

3 oxygen is the right answer .