Which of the following Volatile Organic Compounds (VOCs), a kind of air pollutant, is emitted from natural sources such as plants, bogs etc.?

Terpenes are volatile organic compounds released naturally by plants and bogs.

Formaldehyde is emitted mainly from building materials and combustion, an indoor pollutant.

Benzene comes largely from vehicle exhaust and industrial sources.

Toluene is released from paints, solvents and fuels, all human-made sources.

Only terpene arises chiefly from natural vegetation among these compounds.

Plant terpenes give forests their scent and help form natural aerosols.