Which of the following takes several years to degrade?

A biodegradable substance can be defined as a kind of substance that can be broken down by natural organisms and can be decomposed in a shorter span of time.

Vegetable peels, cotton cloth, and wood can be easily decomposed by microorganisms. Hence, they are biodegradable in nature.

A Non-Biodegradable substance can be defined as a kind of substance that cannot be broken down by natural organism and take several years to decompose.

Plastic bags are non-biodegradable as they take several years to be broken down by microorganisms. 

Hence, plastic bag takes several years to degrade.