Under which one of the following circumstances will heat transfer occur via convection? Group of answer choices Convection occurs within metal objects. Convection only occurs in non-metallic solids. Convection occurs only within a vacuum. Convection occurs in the presence of a liquid or a gas. Convection can occur whether matter is present or not.

1) in metal object heat transfer through the conduction .In vacuum heat transfer through only radiation .

In only gaseous state or in liquid state the heat transfer through convection hence option D is correct

The answer is: Convection occurs in the presence of a liquid or a gas

Explanation:

Convection is a process by which heat is transmitted, either between two liquid or gaseous substances, provided they are at different temperatures.

Heat transfer occurs when there is a temperature gradient between the two bodies that are in direct contact; then, the heat flow flows from the hottest body to the least hot body. Liquids and gases are considered fluids.

it is the second option.