Which of the following is a copolymer among the listed choices?

Introduction / Context:
Copolymers contain two or more distinct monomer species in the same chain. Recognising standard copolymer examples is key for property prediction and processing.

Given Data / Assumptions:

• SBR comprises styrene and butadiene comonomers.
• Neoprene is polychloroprene (homopolymer of chloroprene).
• PVC is a homopolymer of vinyl chloride.

Concept / Approach:
Identify the entry explicitly combining two monomers: SBR. The others are homopolymers in their base forms.

Step-by-Step Solution:
List monomers for each polymer.Select the one with two monomers (SBR).

Verification / Alternative check:
SBR grades vary in styrene content (e.g., 23–25%), tuning glass transition and properties.

Why Other Options Are Wrong:
Neoprene and PVC are homopolymers in standard commercial practice.

Common Pitfalls:
Assuming trade names imply copolymer status; verify monomer list.

Final Answer:
Styrene–butadiene rubber (SBR)