Question

Factory owners could set the terms for work because there was a surplus of...?

Answer 1

There was a demand and a need for work and labour as they were a lot of poverty during this time period. People would almost result to anything for money.

Answer 2

Factory owners could set the terms for work because there was a surplus of labor.

When more people work at a factory, it is easier for the owner(s) to dictate payments, working conditions, equity distribution, and much more. This cannot be done with little amounts of workers because it would be recognized easily.