Wegener formed the theory of continental drift in 1912. what prevented research of the ocean floor, paleomagnetism, and earthquakes at that time?

Well, during that time his theory was not widely accepted by the scientific community; also, lack of technological advancements allowed further research. 

The answer is atmosphere. there are four spheres of the earth: 1. geosphere (from greek word 'geo' = ground), 2. hydrosphere (from greek word 'hydro' = water), 3. biosphere (from greek word 'bio' = life), and 4. atmosphere (from greek word 'atmo' = air). a magnetosphere is a region of space around astronomical objects controlled by the magnetic field of that object. through the process of elimination, since lightning is present in the air, it can be found in the atmosphere.

Idont really understand