The needs to know and to understand

A) are now a part of the basic hierarchy (above self-actualization) .
B) can be stronger than the safety needs.
C) do not appear until middle age.
D) exist only in self-actualized people.

Self-actualization

The realization or fulfillment of one's talents, potential, and capabilities, considered as the ultimate goal of personal development.

Hierarchy

A structure or entity where participants or factions are arranged in sequential order of superiority or command.

Basic Hierarchy

A foundational arrangement or system where entities are ranked or ordered one above the other according to some criterion or authority.