How have geologist determined the shapes of lithospheric plates?Group of answer choicesFossilsMagnetite minerals in igneous rocksEarthquakesNone of the above, geologist have just guessed

Geologists have determined the shapes of lithospheric plates primarily through the study of earthquakes and the magnetic properties of igneous rocks.

1. Earthquakes: The location and frequency of earthquakes around the world provide valuable data about the boundaries of the lithospheric plates. Most earthquakes occur at these boundaries, where plates are either colliding, pulling apart, or sliding past each other. By mapping these earthquakes, geologists can outline the edges of the plates.

2. Magnetite Minerals in Igneous Rocks: When igneous rocks form, the magnetite minerals within them align with the Earth's magnetic field. Over time, as the Earth's magnetic field has periodically flipped, these minerals record these changes. By studying the magnetic properties of these rocks, geologists can determine the rate and direction of plate movement, helping to further define the shapes of the lithospheric plates.

So, the answer is not "Fossils" or "None of the above, geologists have just guessed". The correct answer is a combination of "Earthquakes" and "Magnetite minerals in igneous rocks".