By paying low wages, factory owners were able to

increase their profits in a competitive environment.
avoid overcrowding and accidents on the factory floor.
hire fewer workers to perform a variety of tasks.
promise higher pay as an incentive to work harder.

promise higher pay as an incentive to work harder.

Explanation:

What is wrong with the other choices?

increase their profits in a competitive environment.

You can only increase profits by increasing the price of a good - so that the price exceeds the cost of making the product. Since paying low wages will not affect the profit, this answer choice is incorrect.

avoid overcrowding and accidents on the factory floor.

Lowering wages is unrelated to overcrowding and accidents; therefore this answer choice is incorrect.

hire fewer workers to perform a variety of tasks.

Reducing wages does not enable owners to lay off workers, so this answer is wrong.

answer; legislature;