Flax fibers belong to which fiber category?

• A. Bast fibers
• B. Silk fibers
• C. Mineral fibers
• D. Textile fibers

Answer: (A)

Flax fibers come from the phloem, the bast tissue in the stem, so they are classified as bast fibers. Bast fibers are the strong, long fibers extracted from the plant’s stem tissue just outside the woody core, and they include flax, hemp, jute, and ramie. This category is defined by the plant part they’re sourced from, not by the fabric they make, which is why flax is grouped with other bast fibers rather than with silk (an animal protein fiber), mineral fibers (like asbestos), or seed/leaf fibers (cotton from seeds, sisal from leaves). So flax is best understood as a bast fiber because its origin is the stem’s bast tissue.