Question

The layer below the crust is called _________.
A) mantle
B) plate
C) outer case
D) inner core

Answer 1

Hint : The Earth is composed of four distinct layers. The topmost layer of the Earth is the crust and the most inner layer of the Earth is the core.

Complete step by step answer:
The Earth is divided into different layers based on the composition of different layers. Starting from the center of the Earth, there are four layers which are the inner core, the outer core, the mantle, and the crust.
The inner core has a radius of 1220 km from the centre of the Earth and is the hottest and the densest part of the Earth.
The outer core has a radius of 2880 to 5180 kilometers. The outer core is liquid in form and is also responsible for Earth’s magnetic field.
The mantle which lies just below the crust is the Earth’s thickest layer. It starts beneath 30 kilometres from the surface of the Earth and is where all the tectonic plates are located.
The crust of the Earth is where we stay. It can be as thin as 5 kilometres and as deep as 70 kilometres in some places. The crust also houses some parts of the tectonic planets which are responsible for the formation of continents, mountains as well as causing Earthquakes.
Hence the layer of the Earth below the crust is the mantle which is option (A).

Note:
Except for the crust, no one has ever explored the other layers of the Earth in person. In fact, the deepest humans have ever drilled is just over 12 kilometers. And even that took 20 years and was later abandoned due to high temperatures at that point.