Final answer:
Abraham Maslow is the psychologist who proposed the hierarchy of human needs, ranging from basic physiological needs to the need for self-actualization. This theory is part of humanistic psychology, which focuses on personal growth and fulfillment.
Step-by-step explanation:
The psychologist who developed the idea that human needs are arranged in a hierarchy of importance is Abraham Maslow. Maslow's hierarchy of needs begins with the most basic physiological needs for survival, such as food and shelter. Once these are met, higher-level needs become motivators of behavior, culminating in the need for self-actualization. Maslow's theory is a cornerstone of humanistic psychology, which emphasizes the positive potential of human beings to grow and achieve fulfillment.
Sigmund Freud, Carl Jung, and Ivan Pavlov were also influential figures in psychology but are known for different theoretical contributions. Freud is known for psychoanalytic theory, Jung for analytical psychology, and Pavlov for classical conditioning in behaviorism.