Question

Match List-I with List-II 

List-I (Durability Class)		List-II (Tree Species)
A	Extremely durable wood	I	Syzygium cumini
B	Durable wood	II	Sapium insigne
C	Slightly durable wood	III	Hardwickia binata
D	Perishable wood	IV	Trewia nudiflora

• (A) - (IV), (B) - (I), (C) - (III), (D) - (II)
• (A) - (II), (B) - (III), (C) - (I), (D) - (IV)
• (A) - (III), (B) - (I), (C) - (II), (D) - (IV)
• (A) - (IV), (B) - (III), (C) - (I), (D) - (II)

Hint:

Identifying soft woods used for matchboxes, such as Gutel (Trewia nudiflora), as 'perishable wood' (D - IV) helps you quickly narrow down the options in timber durability matching questions.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
The natural durability of timber is its inherent resistance to decay caused by wood-rotting fungi, termites, and other wood-boring organisms.
Standard graveyard stake tests classify Indian timbers into distinct durability classes.

Step 2: Detailed Explanation:
Let us analyze the natural durability of each species listed:
1. Extremely durable wood: Hardwickia binata (Anjan) yields an exceptionally dense, heavy, and hard red heartwood. It is highly resistant to termite and fungal decay, making it extremely durable even in direct contact with wet soil. Thus, (A) matches with (III).
2. Durable wood: Syzygium cumini (Jamun) yields a durable timber, particularly when submerged in water or used in damp conditions. Thus, (B) matches with (I).
3. Slightly durable wood: Sapium insigne produces soft, low-density wood with limited natural resistance, categorized as slightly durable. Thus, (C) matches with (II).
4. Perishable wood: Trewia nudiflora (Gutel) yields a soft, porous, lightweight wood that is highly susceptible to fungal staining, rot, and insect attacks. It is classified as perishable and is used mainly for packing crates and match splints. Thus, (D) matches with (IV).
This yields the matching sequence: (A) - (III), (B) - (I), (C) - (II), (D) - (IV).

Step 3: Final Answer:
The correct matching sequence corresponds to option (C).