Substances' effects on reaction times from graph data

Steps:

• Examine graph bars: Group 1 (nicotine) has shortest time, indicating fastest reactions.
• Group 2 (alcohol) has longest time, indicating slowest reactions.
• Group 3 (control) has medium time, serving as baseline without substances.
• Conclude nicotine shortens reaction time while alcohol lengthens it compared to control.

Why B is correct:

• Reaction time measures speed from stimulus to response; data shows nicotine decreases it (shorter bar) and alcohol increases it (longer bar), aligning with observed effects.

Why the others are wrong:

• A: Incorrectly labels nicotine as depressant (it speeds reactions) and alcohol as stimulant (it slows them).
• C: Data addresses reaction times, not addiction properties.
• D: Reverses findings—nicotine speeds reactions, alcohol slows them.

Final answer: B