Final answer:
Rehabilitation is often slower for D) older adults, generally those over 65 years of age, due to the decline in physical and cognitive capabilities that comes with advanced aging.
Step-by-step explanation:
Rehabilitation is often slower for the age group represented by older adults. As detailed in the given information, the aging process brings a decline in physical capabilities such as vision, strength, aerobic performance, maximal heart rate, and reaction time, particularly during middle adulthood, which spans from the mid-30s to the mid-60s.
However, once individuals reach the category of older adults, they are subdivided into life-stage groups like young-old, middle-old, and the old-old. The older the age group, typically beyond 65 years of age, the more prominent the physiological and cognitive challenges become.
This can make recovery from illness or injury more complicated and drawn-out due to factors like reduced regenerative capacity, the presence of chronic conditions, and lessened physical resilience.
With advancements in healthcare, older adults may have resources available to assist with rehabilitation, but the slower process is an interplay of numerous biological and psychosocial factors.
Therefore, when considering which age group experiences a slower rehabilitation process, older adults (typically those over 65 years of age) are most likely to have extended recovery periods.