The factors of production are which of the following? a. The land resources, such as natural resources, that are unimproved by human economic activity. b. The outputs generated by the production process of transforming land, labor, and capital into goods and services. c. Labor and capital in industrialized countries, where natural resources are no longer used to produce goods and services. d. Land (natural resources), labor (human capital, entrepreneurship), and capital (constructed inputs such as factories).