What is the leading factor to a producer’s ability to specialize? A. the research about a product
B. the advertising of a product
C. the supply of a product
D. the demand for a product
Plz help it's a tests

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- world peace, cause that's important

- iron man to still be alive, cause i cried my eyes out

- for those in starving places like africa to get the support that they need for food and water, cause they r humans and need those basic things go be alive.