Which of the following best describes clubbing?

• A. Bulbous ends of the fingers with rounded nails
• B. Nails with long ridges along the edge
• C. Flattened nails with concave beds
• D. Pitting of the nail plate

Answer: (A)

Clubbing is the enlargement of the distal digits with nails that become curved and the nail beds appear rounded or beaked. This change reflects increased tissue and vascular growth at the nail bed, often from chronic hypoxia or related systemic conditions. The description “bulbous ends of the fingers with rounded nails” matches this classic sign.

Other nail changes described in the options point to different conditions: long ridges along the nail edge can be page or Beau’s lines in various systemic stresses; flattened nails with concave beds describe koilonychia seen in iron deficiency; pitting of the nail plate is typical of psoriasis.