Step 1: Understanding the Concept:
Alfred Wegener proposed a revolutionary geological theory regarding the Earth's physical evolution.
Step 2: Detailed Explanation:
In 1912, Wegener proposed that all continents were once part of a single supercontinent called "Pangea."
He suggested they had "drifted" apart over millions of years. This is the Continental Drift Theory.
(A) Plate Tectonics is a modern theory that provides the mechanism for continental drift.
(C) Big Bang Theory is about the origin of the universe.
(D) Seafloor Spreading was proposed in the 1960s to support plate movements.
Step 3: Final Answer:
Alfred Wegener proposed the Continental Drift Theory.