I had just finished making a complicated piece of equipment that was to be used for a show opening in Philadelphia called "Fiorello." When the machine arrived they had trouble wiring it, so instead of going off to college that morning for an orientation, I spent several days at the theater fixing my light/sound equipment. The show received poor reviews, except for the mention by one reviewer of the "special effects," which, he wrote, were "outstanding."

Which detail shows that Kamen's piece of equipment really was complicated?

It was used for a show in Philadelphia called "Fiorello."
The show technicians had trouble wiring the equipment.
The show received poor reviews from the critics.
A reviewer wrote that the special effects were outstanding.

The detail that shows that Kamen's piece of equipment really was complicated is that the show technicians had trouble wiring it.

The detail that shows that Kamen's piece of equipment really was complicated is the fact that the show technicians had trouble wiring the equipment.

The detail that shows that Kamen's piece of equipment was complicated is that the show technicians had trouble wiring it. This indicates that the equipment had complex wiring or technical requirements that the technicians found challenging to handle.