Final answer:
The pair most likely to occur together in the same age period in a normative adult life is Erikson's stage of intimacy and low rates of loneliness, which happen during early adulthood.
Step-by-step explanation:
Among the options provided, Erikson's stage of intimacy and low rates of loneliness are most likely to occur together in the same age period during early adulthood. This is the period typically associated with the ages of the 20s through the early 40s. During this stage, many individuals form intimate relationships, including friendships and romantic partnerships, which may lead to lower rates of loneliness. The formation of these social bonds is in line with Erik Erikson's psychosocial stage of 'intimacy versus isolation,' where the main challenge is for adults to develop intimate, loving relationships or risk feeling isolated and lonely.
In contrast to the other pairs mentioned, peak physical functioning and Erikson's stage of generativity do not usually align, as peak physical functioning more commonly occurs in early adulthood, while generativity is a concern of middle adulthood. Noticeable physical decline and fewer but more intense friendships tend to manifest later, in old age. As for maximum division of gender roles and the postparental stage, these do not necessarily coincide with any specific age and are more closely associated with individual life choices and cultural contexts.