Mounting aluminum fins on DIMM modules would be an example of which of the following types of cooling?

Redundant cooling refers to having multiple cooling components (e.g., fans, power supplies with built-in fans) to ensure continuous operation if one fails, which is not what aluminum fins achieve.

Passive cooling relies on materials and design to dissipate heat without requiring external power, fans, or moving parts. Aluminum fins (heat sinks) attached to DIMM modules absorb heat from the memory chips and radiate it into the surrounding air through convection, effectively cooling the module.

A shroud is a cover or enclosure used to direct airflow, typically found with active cooling solutions, but the fins themselves are not a shroud.

Active cooling involves mechanical devices such as fans, pumps, or thermoelectric coolers that actively move heat away from components, which is distinct from the static heat dissipation of aluminum fins.