Which of the following statements with reference to mantle is/are correct ?

1. Moho's discontinuity is at the uppermost part of the mantle.

2. The lower portion of the mantle is called the asthenosphere.

Select the answer using the code given below :

The Earth's interior is divided into three main layers: the crust, the mantle, and the core. The boundary separating the crust from the mantle is called the Mohorovičić discontinuity (or Moho). It marks the transition where seismic waves accelerate, and it is located at the uppermost part of the mantle. Thus, statement 1 is correct.

The mantle is divided into the upper mantle and the lower mantle. The asthenosphere is the highly viscous, mechanically weak, and ductile region of the upper mantle, extending to a depth of about 400 km. It is the primary source of magma that finds its way to the surface during volcanic eruptions. The lower portion of the mantle is generally referred to as the mesosphere. Therefore, statement 2 is incorrect as it wrongly identifies the asthenosphere as the lower portion.