A competitive strategy to be the low-cost provider in an industry works well when

A. price competition among rival sellers is especially vigorous.
B. commodity-based product prevails and minimal differentiation exists.
C. buyers incur low costs in switching their purchases from one seller/brand to another.
D. industry newcomers use low introductory prices to attract buyers and build a customer base.
E. All of these.

E= All of these

Explanation:

As per the Michel Porter Five Forces Model When the competition in industry is very high, substitute product exists, switching costs are very low and there are no entry barriers to enter in market for new suppliers in these scenarios firm must sell their product at low cost.

E) All of these.

Explanation:

When a company decides to compete only based on their low prices that doesn't generally work very well because consumers want to maximize their benefits per dollar, and if the benefits offered are very low, it doesn't matter if the price is also low, consumers wouldn't buy it.

Low price strategies are successful only when a combination of factors are given:

the products offered are homogeneous and the price competition is very intense, leading to perfect substitute products. buyers can easily switch from one product to another, and the benefits they get are similar between competing products.new suppliers also use low introductory prices to try to gain market share.

These are basically the conditions of a perfect competition market, but that rarely happens except with commodities.  

The answer is "IS NOT, NEW, and ECONOMIES OF SCALE".

Explanation:

It is not always intentional if old, and large companies are monopolistic. Market entry could be challenging because new businesses do not find, and an economic scale makes it difficult for such a small new firm to operate as effectively as a large, existing company because of the cause, big old firms benefit throughout the year for the economy of scale reducing costs and boosting earnings. Even though new businesses wish to join that market, they will not do so, because as financing necessary to compete with major customers is insufficient. As just a monopolist, it is not always a matter of course.