Carbon monoxide is almost insoluble in water.

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R

Assertion A :- Carbon forms two important oxides $\mathrm{CO}$ and ${\mathrm{CO}}_2$. $\mathrm{CO}$ is neutral whereas ${\mathrm{CO}}_2$ is acidic in nature.

Reason R :  ${\mathrm{CO}}_2$ can combine with water in a limited way to form carbonic acid, while $\mathrm{CO}$ is sparingly soluble in water.

In the light of the above statements, choose the most appropriate answer from the options given below :-

Carbon dioxide is used,

a. As refrigerant for ice-creams and frozen foods.
b. Extensively to carbonate soft drinks.
c. As a fire extinguisher.

Choose the correct statement(s).