Diminishing returns are a reason that fixed costs remain constant. the marginal cost curve is upward sloping. the average fixed cost curve is downward sloping. the marginal cost curve is downward sloping.

the marginal cost curve is upward sloping.

Explanation:

Utility can be defined as any satisfaction or benefits a customer derives from the use of a product or service.

This ultimately implies that, any satisfaction or benefits a customer derives from the use of a product or service is generally referred to as a utility.

Basically, the marginal utility of goods and services is the additional satisfaction that a consumer derives from consuming or buying an additional unit of a good or service.

For example, buying a candy stick and eating it may satisfy your cravings but eating another one (an additional or extra unit) wouldn't give you as much satisfaction as the first due to diminishing marginal utility.

In Economics, the law of diminishing marginal utility states that as the unit of a good or service consumed by an individual increases, the additional satisfaction he or she derives from consuming additional units would start decreasing or diminishing as the units of good or service consumed increases.

Marginal cost can be defined as the additional or extra cost that is being incurred by a company as a result of the production of an additional unit of a product or service.

Generally, marginal cost can be calculated by dividing the change in production costs by the change in level of output or quantity. A marginal cost curve is upward sloping because of the law of diminishing returns.