Indented vertical lines down the nail plate may be called:

• A. Furrows
• B. Ridges
• C. Patches
• D. Veins

Answer: (A)

Indented vertical lines down the nail plate are furrows. Furrows are grooves that run lengthwise along the nail, creating indentations rather than raised features. This differs from ridges, which are raised lines on the nail, patches which are flat spots or discolorations, and veins which are visible underlying vessels—not indentations. Furrows can appear with aging, dehydration, or mild trauma, and recognizing them helps explain why the nail surface isn’t perfectly smooth. To care for furrows, keep nails moisturized, avoid aggressive filing or trauma, and trim nails gently; if grooves are deep or accompanied by other changes, consider having them evaluated by a professional.