Question

what symptom is one of the most common indicators of nicotine withdrawal?
water retention
muscle twitching
chronic headaches
musculoskeletal system

Explanation:

Nicotine withdrawal symptoms include irritability, craving, headache, etc. Chronic headaches are a common one among them. Water retention is not a typical nicotine withdrawal symptom. Muscle twitching is not a major and common indicator. Musculoskeletal system is a body system, not a symptom.

Answer:

chronic headaches