Final answer:
Shelter, sex, and touch are examples of primary reinforcers, which are innately reinforcing as they satisfy basic biological needs directly, unlike secondary reinforcers.
Step-by-step explanation:
Shelter, sex, and touch are examples of primary reinforcers. A primary reinforcer has innate reinforcing qualities, which means they are not learned and have a natural reinforcing effect. These include basic needs such as food, water, sleep, and touch, which are innately desirable and necessary for survival. Unlike secondary reinforcers such as money or praise, which have no inherent value and only become reinforcing through their association with primary reinforcers, primary reinforcers satisfy biological needs directly. In the context of operant conditioning, primary reinforcers are effective because they fulfil an organism's fundamental physiological requirements, thus reinforcing the behaviour that led to receiving those reinforcers.