Final answer:
By age 65, a person is most likely to lose around 1-2 inches in height due to factors such as osteoporosis and changes in posture. Option a is correct.
Step-by-step explanation:
By age 65, a person is most likely to lose about 1-2 inches of height, which corresponds to option a) 1-2 inches. Height loss in adults can occur due to several factors, including compression of the intervertebral discs, shrinkage of the spine's bones due to osteoporosis, and changes in posture. This phenomenon is more pronounced in women post menopause due to a higher incidence of osteoporosis. However, individual experiences may vary, with some losing slightly more or less than this range.