In the convectional current theory, temperature difference gives rise to what?

Correct answer: Rising and sinking movement

In convectional current theory, a temperature difference produces differences in density within a material. Warmer material generally expands, becomes less dense, and tends to rise. Cooler material becomes relatively denser and tends to sink. The repeated upward and downward movement forms a convection current. In discussions of the mantle, this idea is used to explain how internal heat may drive slow movements of mantle material and contribute to large-scale tectonic processes.

Option C is correct because it directly states the rising and sinking movement produced by the temperature difference. Tides are mainly related to the gravitational effects of the Moon and Sun, while sound waves and rain clouds are not the specific result asked about here. The important chain is temperature difference, density difference, and then upward and downward movement. That chain identifies convection clearly.