Utilitarianism meant:
a)laws interfered with production
b)laws were useful and could be good
c) laws interfered with workers ability to earn wages
d) all people could be useful workers

Of the options given, utilitarianism means laws were useful and could be good (option B).

Explanation:

Utilitarianism is an ethical or moral set of theories that seeks to maximize happiness and wellbeing. The view basically holds that the best law or action is the law or action that produces the most good. Among the most well know philosophers with a utilitarian perspective are Jeremy Bentham (1748–1832) and John Stuart Mill (1806-1873). Bentham is generally considered the first philosopher to really articulate what utilitarianism expounds, which are morals or beliefs that "tends to produce benefit, advantage, pleasure, good, or happiness, (all this in the present case comes to the same thing) or (what comes again to the same thing) to prevent the happening of mischief, pain, evil, or unhappiness to the party whose interest is considered: if that party be the community in general, then the happiness of the community: if a particular individual, then the happiness of that individual" (Bentham, Introduction to the Principles of Morals and Legislation).  These philosophers were interested in how man can achieve the broadest sense of a satisfying and joyous human existence that depends on our human nature more than a moral framework or set of criteria that is external to us.

letter d is correct.