<span>Long after the world to which it belonged has vanished, a habit of thought will live on, indelibly imprinted upon a race or nation, like the footprint of some extinct beast or bird upon a piece of stone.
The word indelibly refers to the anything that is impossible to remove or forget. It is the mark that cannot be erased.</span>
Answer:
- States.
Explanation:
As per the question, the various periods of sleep from quiet sleep to actively moving about and crying would be called '<u>states</u>'. Psychologically, the sleep cycle consists of four to five distinct stages beginning from drowsiness in Rapid Eye Movement to deep non-Rapid Eye Movement sleep. Stage 2 involves the active sleep in which the child is witnessed actively moving and tweaking arms and legs while the 'quiet sleep' is demonstrated as the final stage 5 in which the infant's sleep becomes more sound and progressively deeper. Thus, these periods are characterized as 'states'.