Question

The idea of sea-floor spreading is a part of which theory​

Answer 1

$\huge\mathfrak\pink{Answer}$

$\huge\mathfrak\purple{Theory of continental drift}$

Seafloor spreading disproves an early part of the theory of continental drift. Supporters of continental drift originally theorized that the continents moved (drifted) through unmoving oceans. Seafloor spreading proves that the ocean itself is a site of tectonic activity.

All the best :)