Final answer:
Pathological gambling is best explained by random reinforcement, meaning a variable-ratio reinforcement schedule that leads to the persistence of gambling behaviors. This is supported by neuroscientific evidence showing similar brain activity in gambling and drug addiction, leading to its classification as an addiction in the DSM-5.
Step-by-step explanation:
The best explanation for pathological gambling is B. Random reinforcement, specifically, a variable-ratio reinforcement schedule. Research has revealed that the behavioral persistence in gambling is associated with this type of reinforcement. The release of neurotransmitters like dopamine and norepinephrine during gambling episodes, even in the case of near misses, sustains the engagement and compulsion in pathological gamblers. This is due to the activation of reward centers in the brain, making the behavior very persistent and similar to that seen in substance addiction. The DSM-5 now recognizes gambling as an addiction, partly because of these neuroscientific findings that draw parallels between gambling-related brain activity and the effects produced by addictive drugs.