What makes a desire for a product effective demand?

### Why this is right Demand in economics is effective desire: a consumer must want the good and have the ability to pay. Wanting something without purchasing power is not effective demand in this definition. ### The concept Individual demand describes one buyer’s quantities at different prices over a period. Market demand combines quantities demanded by all buyers in a market. Demand is distinct from supply, which describes sellers’ willingness to offer quantities for sale. ### The other options - **The buyer has heard of the product**: awareness alone does not establish willingness and ability to buy. - **The seller has produced the product**: production concerns supply, not buyers’ demand. - **The product has a high price**: price alone does not show that consumers want and can afford it. ### Remember Effective demand requires both desire and purchasing ability.