What does the law of equi-marginal returns state?

The law of equi-marginal returns, often referred to in the context of consumer choice, states that a consumer maximizes their total utility when the ratio of marginal utility to price is the same for all goods consumed. This means that a rational consumer will allocate their resources in such a way that the additional satisfaction (marginal utility) gained from spending the next unit of currency on each good is equalized.

In practical terms, if a consumer finds that they are receiving more satisfaction per euro spent on one good compared to another, they will reallocate their spending until the ratios align. This behavior ensures that they are getting the best overall utility from their limited income. Such an optimization condition underlies the choice theory, where consumers are assumed to act rationally to achieve maximum satisfaction given their budget constraints.

The other options do not accurately describe the principles underlying consumer choice or the concept of utility maximization as laid out by this law. The focus on equalizing the marginal utility per unit of currency spent is key to understanding consumer behavior in economics.