Final answer:
The technological innovation that was not central to the ability to fly heavier-than-air aircraft is the teardrop wing shape. Option C is correct.
Step-by-step explanation:
The technological innovation that was not central to the ability to fly heavier-than-air aircraft is the teardrop wing shape.
In the late 19th and early 20th centuries, the Wright brothers conducted experiments with kites and gliders to understand how to create controllable airplane designs. They developed a technique called wing-warping, which involved bending the wings to cause the aircraft to bank and move up and down.
They also discovered how to control an aircraft in turns by using a adjustable rudder. These innovations were crucial in enabling the ability to fly heavier-than-air aircraft.
On the other hand, the teardrop wing shape, although used in some aircraft designs, is not central to the ability to fly. It is primarily used to reduce drag and increase fuel efficiency in certain types of aircraft, but it is not essential for achieving flight.