The correct answer to this open question is the following.
Although there are no options attached, or there is no specific time in history, we can comment on the following.
If you refer to the original industrial giants during the Gilded Age, yes, we could say that they were good examples of free enterprise. However, as we know, they used questionable practices such as the creation of monopolies that affected the industry of the time. That is why it was necessary reformation to create laws to allow more competence.
If you refer to modern America industrial companies, yes, they are examples of the free enterprise system that includes the freedom to participate in any kind of business, the right to own property or a business and to make a profit from it, to participate in a competitive market, and to honor consumers.