Question

which invention in the mid - 20th century helped validate wegeners theory of continental drift? satellite imaging radiosonde deep - sea drilling sonar

Explanation:

Sonar (Sound Navigation and Ranging) was used to map the ocean floor in the mid - 20th century. The mapping of the ocean floor, including the discovery of mid - ocean ridges and the pattern of magnetic stripes on the ocean floor (which was related to seafloor spreading, a key part of the theory that supported continental drift), was made possible by sonar technology. Satellite imaging became more prominent later, radiosondes are for atmospheric measurements, and deep - sea drilling (while important for geological studies) was not as foundational as sonar in the initial validation of the concepts related to continental drift through seafloor spreading evidence.

Answer:

Sonar