Which of the following is not the theory of intelligence?

Let's review the psychological frameworks listed in the options:Unifactor theory: Proposed by Alfred Binet, treating intelligence as a singular, indivisible mental capacity.Two-factor theory: Proposed by Charles Spearman, dividing intelligence into general ability ($g$ -factor) and specific abilities ($s$ -factor).Multifactor theory: Proposed by Edward Thorndike, stating that intelligence consists of various independent distinct micro-abilities.Theory of regression: This is a core biological principle formulated by Sir Francis Galton regarding the inheritance of physical traits (the tendency for offspring of extreme parents to deviate back toward the population mean). It is also a statistical modeling technique, not a cognitive theory explaining human intelligence.