The answer is option C "Warm air rises as cooler, denser air falls." Convection is heat transfer between two objects for example a hot metal pot to a spoon. During convection hot air rises and cold air (or denser air) sinks.
Hope this helps.
I believe it would be Rhizobium bacteria
They both exhibit imperfect competition in that oligopoly has few sellers while monopoly has many sellers.
Or you can say
Firms have some level of control over prices in both competitive structures.
What’s the question.....................
