When focusing on a near object,

  1. suspensory ligaments tighten
  2. ciliary muscles relax and the lens becomes thinner
  3. the iris closes
  4. ciliary muscles contract and the lens becomes fatter
Answer

D) ciliary muscles contract and the lens becomes fatter

Near focus needs a thick, more convex lens. O Level Biology · Topic 14 Coordination and Control · 14.2 Mammalian sense organs

Biology MCQ · More O Level Biology: Coordination and Control MCQs · Practise