When using horizontal differentiation, a firm divides itself into subunits based on function, type of business, or Multiple Choice location of competition. level of difficulty. employee skill-level. geographic area.

Geographical area

Explanation:

Product differentiation which is based upon different functionality is referred to as Horizontal differentiation.

Product differentiation refers to a mechanism whereby a manufacturer makes his product unique and slightly different from similar products offered in the market by competitors. Such an attribute helps a customer in product identification.

Product differentiation can be achieved by different packaging, changing product appearance, product quality or added functionality.

Horizontal differentiation takes place when products which belong at the same level differ slightly based upon different functions or uses they offer.

While a firm uses horizontal differentiation for it's products, it divides itself into subunits based upon functions , type of business and geographical area. It means each subunit focuses on it's own functions i.e the kind of differentiated products the sub unit shall produce, serving the requirements of a specific geographical area.

metallurgy is your answer

the "study of metals and the process of refining ("

note that it says metal. metallurgy has the word "metal" in it, and so is most likely your answer (and is your answer).

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