Supply refers to the complete amount of a given commodity or service that is available to consumers. Hence appropriate option is B
What do you mean by demand and supply?
The number of people wanting and able to acquire things at various prices during a certain period of time is known as demand. The desire to get a thing, as well as the readiness and capacity to pay for it, are all indicators of demand for any item.
If depicted on a graph, supply can refer to the quantity available at a single price or the amount available throughout a range of prices.
Therefore ,
Grace and her sister are referring to the amount of product that is available for purchase by Supply.
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