Mental-model theory turns deduction into spatial inspection

Correct: B — Constructing concrete spatial-token models of premises and inspecting them

Mental-model theory predicts that reasoning difficulty scales with the number of distinct models a premise set licenses, not with the number of formal-logic steps required. Two-model problems are reliably harder than one-model problems even when the formal derivation is the same length. The theory accounts for systematic errors — people tend to consider an initial model and miss alternatives — and is contrasted with mental-rules theories (Rips, Braine). Functional-imaging supports a parietal/spatial substrate consistent with token-manipulation accounts.