Correct Option
The correct option isThe cocoons of silk worms
Explanation
Sericulture is the commercial rearing of silkworms for the production of silk. Silk is a natural protein fiber produced by the larvae of certain insects to form cocoons.
Statement-wise Analysis
- The bark of the mulberry tree is Incorrect: The bark or leaves of the mulberry tree serve as the primary food source for the silkworm larvae (specifically Bombyx mori). While essential to the process, the plant itself does not yield the silk fiber.
- The cocoons of silk worms is Correct: Raw silk is extracted directly from the cocoons spun by the larvae of silkworms. The larva secretes a protein called fibroin, which hardens on exposure to air, forming the silk filament used to create the cocoon.
- The stem of the flax plant is Incorrect: The stem of the flax plant is the source of linen fiber, which is a cellulosic plant fiber, not an animal protein fiber like silk.
- The cotton bolls found in Central Asia is Incorrect: Cotton bolls are the protective cases around the seeds of the cotton plant. They yield cotton fiber, which is cellulosic in nature.
Key Takeaway
Silk is an animal fiber obtained from the cocoons of silkworm larvae, whereas cotton and linen are plant-based fibers derived from bolls and stems, respectively.