The compound which shows metamerism is:

Metamerism arises due to the difference in the nature of alkyl groups attached to the same polyvalent functional group (like $-O-$, $-S-$, $-NH-$, $-CO-$).${\text{C}}_4{\text{H}}_{10}\text{O}$ can represent ethers:Ethoxyethane: ${\text{CH}}_3{\text{CH}}_2-\text{O}-{\text{CH}}_2{\text{CH}}_3$ 1-Methoxypropane: ${\text{CH}}_3-\text{O}-{\text{CH}}_2{\text{CH}}_2{\text{CH}}_3$ Since these differ in the alkyl groups on either side of the oxygen atom, they are metamers.