The balanced chemical reaction for the following reaction is:

 $C_3{H}_8+O_2\to C{O}_2+H_{2}O$

A chemical equation is a representation of a chemical process using symbols (substances). Reactants, products, and an arrow indicating the direction of the reaction and the product make up a chemical reaction or equation. A balanced chemical equation is one in which all of the molecules on both sides of the reaction have the same number of atoms.

The rule of conservation of mass governs how a chemical equation balances. The total mass of each element involved in a chemical reaction should match the total mass of each element present on the product side since the rule of conservation of mass states that mass cannot be generated or destroyed in a chemical reaction. An imbalanced chemical equation is one in which a chemical reaction does not adhere to the rule of conservation of mass.

First, we need to balance the elements other than oxygen and hydrogen on both sides.

$C_3{H}_8+O_2\to 3C{O}_2+H_{2}O$

Now, balance the number of hydrogens on both sides:

$C_3{H}_8+5O_2\to 3C{O}_2+4H_{2}O$

Lastly, balance the number of oxygens on both sides:

$C_3{H}_8+5O_2\to 3C{O}_2+4H_{2}O$

Hence, option A is correct.