All combustion reactions are oxidation-reduction reactions. If true enter 1, else enter 0.
(A) 1
(B) 0

Hint: Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke.

Complete step by step solution:
We have been asked that all the combustion reaction, are oxidation-reduction reaction,
So, for that,
Combustion is the scientific word for burning. In a combustion reaction a substance reacts with oxygen from the air and transfers energy to the surroundings as light and heat. The products of a combustion reaction are called oxides.
Let’s take an example:
\[C{{H}_ {4}} +2{{O}_ {2}} \to C{{O}_ {2}} +2{{H}_ {2}} O\]
Methane burns in the presence of oxygen to produce carbon dioxide and water. This process of combustion releases energy. When energy is released during the course of a chemical reaction, it is said to be an exothermic reaction.
The oxidation number of elemental C and oxygen are 0 each.
The oxidation number of C in $C{{H}_ {4}} $ is -4, and that in $C{{O}_ {2}} $ +4,
So, carbon is getting oxidised,
The oxidation number of O in ${{O}_ {2}} $ is 0 and that in $C{{O}_ {2}} $ is -2,
So, oxygen is getting reduced.
Hence, we can say that combustion reaction is oxidation-reduction reaction.

So, we can conclude that option (A) is correct.

Note: Redox is a type of chemical reaction in which the oxidation states of atoms are changed. Redox reactions are characterized by the actual or formal transfer of electrons between chemical species, most often with one species undergoing oxidation while another species undergoes reduction.