I thought… a-c is isobaric and isothermal compression from a gas to a liquid, and c-d…

I thought… a-c is isobaric and isothermal compression from a
gas to a liquid, and c-d is adiabatic compression from a liquid to
a solid.
Am I correct? If not, please can you explain the correct
answer? Thanks very much.

The diagram shows a generic pVT surface of a substance. The substance is taken on a journey’ across the pVT surface from point ‘a’ to point ‘d’ via two different processes. Describe the two different processes and give details of the phase (or phases) of the substance present at each stage. Where appropriate, discuss how the relative amounts of the phases present change. [5 marks]