The correct answer is: A. Relationship between revenue and costs at various levels of output.
A break-even chart is a graph that shows the relationship between revenue and costs at various levels of output. It is a useful tool for businesses because it can help them to determine the level of output at which they will break even, or the point at which their revenue equals their costs. This information can be used to make decisions about pricing, production, and marketing.
Option B is incorrect because it is the volume or output level at which the enterprise break-even. This information is useful, but it is not the most useful information derived from a break-even chart.
Option C is incorrect because it is the amount of sales revenue needed to cover enterprise variable costs. This information is useful, but it is not the most useful information derived from a break-even chart.
Option D is incorrect because it is the amount of sales revenue needed to cover enterprise fixed costs. This information is useful, but it is not the most useful information derived from a break-even chart.