In materials science and textile technology, rayon is a man made fibre described as regenerated cellulose. From which raw material is rayon originally obtained before it is chemically processed into fibre form?

Introduction / Context:
Rayon is one of the earliest man made fibres used in the textile industry and is often referred to as artificial silk because of its shine and drape. However, unlike purely synthetic fibres such as nylon and polyester, rayon is made from a natural source that is chemically processed. This question tests whether you know the original raw material from which rayon is produced before conversion into filaments and yarns.

Given Data / Assumptions:

• Rayon is a man made or semi synthetic fibre, not a fully synthetic polymer.
• It is described as regenerated cellulose in many textbooks.
• Cellulose is a structural polysaccharide found in plant cell walls.
• The options list several natural fibres and one plant derived industrial product.

Concept / Approach:
Rayon is manufactured by chemically treating cellulose obtained from wood pulp or, in some cases, from cotton linters. The cellulose is dissolved in suitable chemicals to form a viscous solution which is then forced through spinnerets to form filaments. These filaments are hardened and converted into fibre. Because the cellulose originally comes from wood pulp, rayon is classified as a regenerated cellulose fibre, sitting between natural fibres and fully synthetic fibres. Silk, wool and cotton are all natural fibres in their final form, not intermediate raw materials for rayon production.

Step-by-Step Solution:
Step 1: Recall that rayon is made by chemically processing cellulose, and is therefore called regenerated cellulose. Step 2: Identify which option contains a material rich in cellulose that can be processed industrially in large quantities. Step 3: Recognise that wood pulp, obtained from trees, is a major industrial source of cellulose for paper and fibre production. Step 4: Note that silk and wool are animal fibres already in final usable form, and cotton is a plant fibre used directly as a textile, not typically processed into rayon in common textbook examples. Step 5: Conclude that wood pulp is the correct raw material from which rayon is produced.

Verification / Alternative check:
Textile science references and school level science books explain the viscose process for rayon manufacture. In this process, cellulose from wood pulp is treated with sodium hydroxide and carbon disulphide to form cellulose xanthate, which is dissolved to create viscose solution. This solution is extruded through spinnerets into a coagulating bath, regenerating cellulose as fine filaments known as rayon. The repeated emphasis on wood pulp and regenerated cellulose confirms that wood pulp is the primary raw material named in examination style questions.

Why Other Options Are Wrong:
Option a, silk, is itself a natural protein fibre produced by silkworms and is not used as a starting material for rayon.

Option c, wool, is a keratin based animal fibre from sheep and other animals and is not processed into rayon in standard industrial practice.

Option d, cotton, is a natural cellulose fibre used directly in spinning and weaving; while cotton linters can be a source of cellulose, school level questions usually emphasise wood pulp as the answer.

Common Pitfalls:
Learners sometimes confuse rayon with silk because rayon is marketed as artificial silk and feels similar, which may tempt them to choose silk as the source. Others may choose cotton because both cotton and rayon are cellulose based, but they overlook the industrial emphasis on wood pulp in textbook descriptions. Remembering the phrase regenerated cellulose from wood pulp is a reliable way to recall the correct raw material during exams.

Final Answer:
Rayon is obtained by chemically processing cellulose from wood pulp.