I believe the answer is: the nonmaterial component of Korean culture.
Non material component of a culture refers to component of the culture that we could not physically touch. This could include things such as gestures, language, values,folkways, norms and mores. In the example above not covering bodies with towel is influenced by norms rather than the towel.
The answer is Psychological Processes.
To complete the sentence (second):
This led him to suspect that these symptoms resulted from psychological processes.
Quick information:
Psychological processes are used during acquisition. The most basic psychological processes are sensation, perception, attention, learning, and memory.
Answer:The Huang He was isolated from other places and people by its geography.
Explanation:
A