Correct option is C
Preservation of Timber:
The main objectives of such treatment are to ensure a longer and durable life of timber, and protect the timber from the attack of fungi and insects etc.
Most timber preservatives are essentially fungicides and need the addition of an insecticide to make them suitable for use against termites and other insects.
Chemical compounds such as Dichloro-diphenyl trichloro-ethane (DDT) are applied on wood for the prevention from insects.
Types of Preservatives used in Timber:
1. ASCU treatment
2. Organic solvent preservative
3. Water soluble preservative
4. Creosote Oil
