28 According to 14 CFR part 107, who is responsible for determining the performance of a small unmanned aircraft?
"Operator" is not the pilot. Operator has a specific meaning within the FAA, and it is not necessarily the pilot.
This is not the correct answer.
Operator does, most of the time, mean the owner. But not always. For example, Donald Trump leases his jet. The owner is the leasing company. The operator is the company that flies and maintains the aircraft, and the pilot is employed by the operator. United Airlines is another example of an aircraft owner/operator.
In the small UAS world, the owner/operator and pilot will most often be one individual.