Question

what is the definition of convection
transfer of thermal energy by direct contact of two objects or portions of matter
tendency of particles to spread out when the kinetic energy increases
a type of thermal energy transfer in which currents carry thermal energy from one part of the fluid to another
sum of the kinetic energies of all the particles that make up an object

Explanation:

Convection is a mode of heat transfer. It occurs in fluids (liquids and gases). When a fluid is heated, it expands, becomes less dense, and rises. The cooler, denser fluid then sinks to take its place. This creates a circular motion (current) that transfers thermal energy. The key elements are thermal energy transfer, fluids, and currents.

Answer:

a type of thermal energy transfer in which currents carry thermal energy from one part of the fluid to another