Answer: What has genetic engineering been used to produce?
Explanation: A
It’s part of the upper mantle just below the lithosphere. Rocks in the asthenosphere are “plastic” meaning they can flow in response to deformation (like silly putty). It’s highly viscous, mechanically weak and ductilely deforming region of the the upper mantle.
It's the first one where it resist change in pH solutions by neutralizing :)