Statement: “Performing complex mental tasks while driving is dangerous.” — a psychologist.\nAssumptions:\nI. Increased cognitive load reduces the driver’s ability to detect hazards and react safely.\nII. Hands-free phone conversations can be as safe—or as risky—as talking to a passenger, depending on the conversational demands.\nIII. Human insecurity is a man-made problem.

Introduction / Context:
The statement asserts a general safety principle: cognitive distraction impairs driving. We must identify which assumptions logically underpin this claim among the given options.

Given Data / Assumptions:

• I posits the mechanism: high mental workload → degraded hazard perception/response.
• II gives an applied comparison: risk equivalence between hands-free calls and in-car conversations depends on cognitive demand, not the device.
• III is unrelated to driving psychology.

Concept / Approach:
To say “complex mental tasks while driving are dangerous,” one must accept that cognitive load interferes with driving performance (I). The hands-free vs passenger comparison (II) is a common implication used to counter the notion that “hands-free is safe”; it supports the idea that mental demand (not just manual) drives risk, coherently undergirding the general claim.

Step-by-Step Solution:
1) I articulates the core causal channel; without it, the claim lacks mechanism.2) II reinforces that mental task demand, irrespective of modality, can impair safety, which is consistent with and supportive of the thesis.3) III is irrelevant; it does not bear on distraction or driving risk.

Verification / Alternative check:
The generalization remains credible when risk is tied to cognitive demand across contexts — precisely what II illustrates.

Why Other Options Are Wrong:
Options including III bring in an unrelated theme; options excluding I miss the central mechanism.

Final Answer:
Only I and II.