Which of these is NOT a characteristic of Yan organs?

The option that identifies a characteristic that is NOT attributed to Yang organs is the tendency to store. Yang organs, such as the heart, lungs, liver, and spleen, are primarily involved in dynamic processes that support the body's immediate physiological activities, rather than functions related to storage.

Typically, Yang organs have a solid structure and play a crucial role in digestion. For instance, they are responsible for breaking down food and assimilating nutrients, which implies a direct involvement in the digestive process. Additionally, Yang organs have roles in the excretion of waste. They continuously process substances to produce energy and eliminate byproducts.

In contrast to these functions, the characteristic of storage is more accurately associated with Yin organs. Yin organs, such as the kidneys, liver, and spleen, are known for their ability to store substances, like blood and fluids, rather than for processing or excreting them. This fundamental difference highlights the dynamic versus storage functions that differentiate Yang organs from Yin organs in Traditional Chinese Medicine. Thus, the emphasis on dynamic processes aligns with the characteristics of Yang organs, confirming the correctness of the answer regarding storage tendencies.