Respuesta :
The additional evidence was Seafloor Spreading Processes that led to the development of the theory of plate tectonics.
Seafloor Spreading Processes:
It is the spreading of tectonic plates ( large slabs of Earth's lithosphere), split apart from each other.
Seafloor spreading processes is the result of mantle convection, in which less-dense material rises and form a mountain or elevated area of the seafloor.
Therefore, the additional evidence was Seafloor Spreading Processes that led to the development of the theory of plate tectonics.
To know more about plate tectonics.
https://brainly.com/question/19869870