What was Mohorovičić's observation?(1 point) Responses Seismic waves penetrated all Earth's layers. Seismic waves penetrated all Earth's layers. Seismic waves travelled at constant speeds. Seismic waves travelled at constant speeds. Seismic waves could not go through the brittle crust. Seismic waves could not go through the brittle crust. Seismic waves travelled at varying speeds.

Answer 1

Mohorovičić's observation was that seismic waves travelled at varying speeds when they passed through different layers of the Earth. This led to the identification of the Mohorovičić discontinuity (often referred to as the Moho), which is the boundary between the Earth's crust and the underlying mantle.