What sign may indicate that a client has a fungal nail infection?

The presence of thickened nails with discoloration is a classic sign of a fungal nail infection. Fungal infections often lead to changes in the texture and appearance of the nail. The nails may become dense and more brittle, and discoloration can range from yellow to brown. These characteristics result from the fungus affecting the nail bed and plate, disrupting normal growth and causing the nail to become abnormal in appearance.

In contrast, other options such as a bright pink color, localized swelling, and consistent nail growth do not typically point to a fungal infection. A bright pink color is usually a sign of healthy nail growth, while localized swelling could indicate other issues, such as an injury or an inflammatory condition, rather than a fungal infection. Consistent nail growth suggests that the nail is functioning normally, as fungal infections might inhibit growth or cause distortion. Thus, thickened nails with discoloration is the most telling sign of a fungal nail infection.