What was Mohorovičić's observation?(1 point)%0D%0AResponses%0D%0A%0D%0ASeismic waves penetrated all Earth's layers.%0D%0ASeismic waves penetrated all Earth's layers.%0D%0A%0D%0ASeismic waves could not go through the brittle crust.%0D%0ASeismic waves could not go through the brittle crust.%0D%0A%0D%0ASeismic waves travelled at constant speeds.%0D%0ASeismic waves travelled at constant speeds.%0D%0A%0D%0ASeismic waves travelled at varying speeds.

Answer 1

Mohorovičić's observation was that seismic waves travelled at varying speeds. This observation led to the discovery of the Mohorovičić discontinuity (or Moho), which is the boundary between the Earth's crust and the underlying mantle.