Among common refinery products—naphtha, kerosene, low-sulphur heavy stock (LSHS), and furnace oil—identify which typically contains the minimum sulphur under normal processing and product specifications.

Introduction / Context:
Sulphur in petroleum products affects emissions, catalyst life, and product quality. Different fractions exhibit different sulphur levels based on crude slate and extent of hydrotreating. This question asks you to pick the product that, in practice, has the lowest sulphur content among typical marketed fuels.

Given Data / Assumptions:

• Products compared: naphtha, kerosene, LSHS, furnace oil.
• Typical modern refining includes hydrotreating of light streams.
• “Minimum sulphur” refers to typical finished product specifications from a standard fuels refinery.

Concept / Approach:
Light fractions such as naphtha are readily hydrotreated to very low sulphur levels (often to near-zero for petrochemical feed specs). Kerosene is also commonly hydrotreated, but specs can be higher than for petrochemical-grade naphtha. Heavy stocks like furnace oil and even LSHS retain substantially more sulphur than light hydrotreated streams, despite “low-sulphur” labeling relative to other heavy fuels.

Step-by-Step Solution:

Verification / Alternative check:
Refinery product specifications and hydrotreating outcomes show naphtha achieving the lowest sulphur targets (especially when destined for reforming/petrochemicals).

Why Other Options Are Wrong:

Common Pitfalls:
Letting the “low-sulphur” label of LSHS mislead you; it is low relative to other heavy fuels, not relative to light hydrotreated streams.

Final Answer:
Naphtha