Final answer:
The statement that 'Ability to have quality of life is related to cognitive function' is most true about psychological aging. Maintaining cognitive function is essential for quality of life, and planning for the future and social connectedness are also important aspects of successful aging. Conversely, disengagement is generally not seen as beneficial for psychological health.
Step-by-step explanation:
The question asks about the truths regarding psychological aging, particularly as it pertains to different theories of aging and the aspects that contribute to successful aging. Among the options given, the statement, "C. Ability to have quality of life is related to cognitive function," is most true about psychological aging. This is supported by research indicating that cognitive function is crucial for maintaining quality of life as one ages. Cognitive impairments can lead to difficulties in performing daily activities and may progress to more severe conditions like dementia. Cognitive rehabilitation and maintaining an active, engaged lifestyle are key elements in preserving brain health and quality of life.
Planning for the future is another essential aspect of successful aging, as getting older often requires adjustments in one's lifestyle and goals. It suggests that older individuals might need to adapt their activities to conserve their energy for the most meaningful pursuits, which aligns with continuity theory. This theory offers a contrast to disengagement theory, which posits that withdrawing from society and social relationships is a natural part of growing old. Social connectedness and support play significant roles in aging well, and disengagement tends to be seen as less beneficial for psychological health when compared to continued engagement.