Answer: Option (a) is the correct answer.
Step-by-step explanation:
Convection is defined as the process in which a fluid (liquid or gas) when heated then more dense (cooler) substance sinks ate the bottom whereas less dense (hotter) substance will rises at the top.
For example, boiling of cold water.
On the other hand, solid substances are able to transfer heat through the process of conduction and not convection.
Conduction is defined as a process in which two objects of different temperature are placed adjacent to each other then there will occur transfer of heat from hotter object to colder object till their temperature becomes equal.
Thus, we can conclude that solid state of matter is least likely to transfer heat by convection.