Which of the following conditions involves redness and inflammation of the nail bed?

The condition that involves redness and inflammation of the nail bed is paronychia. Paronychia is an infection of the skin around the nail, typically caused by bacteria or fungi, which leads to symptoms such as redness, swelling, and possible pain at the site. This inflammation often occurs when the skin barrier is compromised, such as through hangnails, nail biting, or excessive exposure to moisture.

In contrast, onychomycosis refers to a fungal infection of the nails that usually leads to discoloration, thickening, and separation of the nail from the bed but does not specifically cause inflammation of the nail bed. Onycholysis describes the separation of the nail from its bed, which can occur due to various reasons, but is not characterized by inflammation or redness. Aging may cause various changes in the nails, such as brittleness or discoloration, but it does not specifically involve inflammation of the nail bed. Thus, the distinct symptoms and characteristics associated with paronychia make it the correct choice for identifying a condition involving redness and inflammation of the nail bed.