B.F. Skinner determined that nearly all behavior is determined by

1) classical conditioning.
2) hierarchical needs.
3) operant conditioning.
4) self reflection.

3) operant conditioning.

B.F. Skinner determined that nearly all behavior is determined by:

3) operant conditioning.

B. F. Skinner, a pioneer in psychology, is best known for his work in the field of behaviorism. He believed that nearly all behavior is determined by operant conditioning. To understand why Skinner determined this, let's first explain what operant conditioning is and how it works.

Operant conditioning is a type of learning that occurs through consequences of actions. It involves the association between a behavior and the consequences that follow. According to Skinner, behavior that is reinforced (rewarded) tends to be repeated, while behavior that is punished or not reinforced tends to decrease.

To determine that nearly all behavior is determined by operant conditioning, Skinner conducted numerous experiments, most notably with animals such as rats and pigeons. He developed a device called the operant conditioning chamber, also known as the Skinner box, in which an animal could receive rewards or punishments for specific actions. Through these experiments, he demonstrated that animals (and humans) could learn and modify their behavior based on the consequences they experienced.

Skinner's research and theories challenged the prevailing notion that behavior is primarily driven by internal factors or innate traits. He argued that external factors, specifically the consequences of behavior, are the primary determinants of our actions. This belief led him to conclude that almost all behavior can be explained and understood through the principles of operant conditioning.

Therefore, the answer to your question is 3) operant conditioning. Skinner determined that the consequences of our actions play a significant role in shaping and determining our behavior.