Which one of the following statements best describes the term 'Social Cost of Carbon' ? It is a measure, in monetary value, of the long-term damage done by a tonne of CO2 emissions in a given year.

Explains a carbon tax is levied based on the amount of carbon contained in a fuel — showing a policy that attaches a monetary value to CO2 quantity.

A student could compare the idea of a tax-per-tonne to the concept of a monetary cost-per-tonne and ask whether that cost is intended to reflect damages (social cost) rather than simply revenue or behaviour change.

States carbon offsets are quantified and sold in metric tonnes of CO2e, i.e., a market price is assigned to each tonne of avoided emissions.

Use market prices for one tonne of CO2e as examples to test whether a single monetary value can represent the long-term damage per tonne.

Defines carbon credit as earned when an organisation reduces emissions by one tonne of CO2e — linking one-tonne units to tradable monetary instruments.

A student could examine how credit pricing attempts to internalise externalities and whether that pricing is set to reflect long-term damages per tonne.

Gives an example comparing emissions from a thermal plant versus a wind plant and mentions investment/trading to avoid emissions — illustrating monetary choices tied to tonnes of emissions avoided.

Compare the cost of investing in low-emission alternatives per tonne avoided to estimates of damages per tonne to see if they align with the supposed 'social cost'.

Describes a Clean Energy Cess and later a Compensation Cess on coal production expressed per tonne — an explicit monetary charge tied to a unit of carbon-containing fuel.

A student could use such per-tonne charges as proximate examples to ask whether they were designed to reflect long-term social damages (social cost) or other policy objectives.