Concept:The cigarette filter removes nicotine particles from smoke by trapping them on the surface of the filter material.Explanation:The filter contains fine particles like activated carbon.These particles have a large surface area.Nicotine in the smoke is held on the surface of these particles.This surface trapping process is called adsorption.It is different from absorption, which involves soaking into the whole material.The filter does not burn or evaporate the nicotine.Answer:B. adsorption