A major characteristic of natural resources is they

Analyze the question: It asks for a major characteristic of natural resources. Natural resources are things like land, crude oil, forests, rivers, minerals, and sunlight, which are part of the factor of production called "land."

Explain the concept: In Economics, natural resources are materials and conditions that occur in nature and were not made by human effort. Their key features are:

• They are provided by nature, not produced by man.
• Their supply is generally fixed or limited, though some are renewable.
• They are immobile in some cases (e.g., land and minerals).
• They have no cost of production because nature supplies them. Their usefulness comes from being extracted or developed.

Step-by-step evaluation of the options:

• A. Are unlimited in supply: Wrong. Natural resources are scarce. Crude oil, for example, can be exhausted, and land is fixed in supply.
• B. Have high cost of production: Wrong. Natural resources are not produced by humans, so they have no production cost. Extraction does cost money, but that is not the same thing.
• C. Are free gifts of nature: Correct. Natural resources exist without human effort, which is why Economics describes land and its resources as "free gifts of nature."
• D. Do not command any price: Wrong. Many natural resources do command prices. Oil, gold, and land are sold at high prices because they are scarce and useful. Being a free gift from nature does not mean the resource sells for free.

Tip: Remember the phrase "Land = free gift of nature." If an option says "unlimited," be suspicious, because Economics is built on scarcity. Also watch out for option D, which is a common trap: "free gift" describes how the resource originated, not whether it has a market price.