Economies of scale arise when a. an economy is self-sufficient in production. b. individuals in a society are self-sufficient. c. fixed costs are large relative to variable costs. d. workers are able to specialize in a particular task

d. workers are able to specialize in a particular task.

Explanation:

In Microeconomics, economies of scale can be defined as cost reductions or cost advantages that arises when a business entity is increases its  production or are large in size.

This ultimately implies that, when an organization chooses a convenient scale of operation or reduce its scale of production, this would lead to a reduction in the cost of production and consequently, some benefits such as lower long-run average cost, increased sales, profits and lower cost price for the consumers of these finished products.

Generally, economies of scale arise when workers are able to specialize in a particular task. This is so because having a good number of professionals and experts would increase the level of production or output, as they are quite conversant with the best method of production, time management and efficiency.

i mean they dont have to