Fibres obtained from plants and animals are called:

Cellulose fibres are found in both plants and mammals. These may be physically and chemically processed to create fibres with a variety of characteristics.

Fibers are cellulose that has been changed or transformed and is derived from natural sources. Plants and animals are both natural sources. To separate the required fibre from the unprocessed material, the cellulose derived from these sources is subjected to chemical processing.
Natural fibres are those that are derived from plants and animals. In order to create textiles and papers, fibres are discovered to be very thin, thread-like strands. Cotton and jute are two popular plant-based fabrics. Wool and silk are the most popular fibres made from animals.

The fibres that people have created themselves are known as man-made fibres. They are prepared to raise the calibre of fibres made from organic materials. They are referred to as synthetic fibres as well. Polyester, polyamide, polypropylene, and other synthetic fibres are often used.
Organic fibres are crystalline polymer fibres with a high level of strength. High performance fibres is another term for them. Applications for textiles frequently employ organic fibres. The most popular organic fibres, which are organic polyamides, are aramid fibres. They have minimal heat conductivity and great rigidity and strength.

Hence, the correct option is (B).