Achluophobia is the specific fear of darkness or night. The term comes from Greek 'achluo' (darkness) and 'phobos' (fear). This is distinct from nyctophobia (fear of night), though they're related. People with achluophobia may experience anxiety, panic attacks, or sleep disturbances when in dark environments. The other options represent different fears: apiphobia (bees), aurophobia (gold), and aviophobia (flying).