Individuals who weathered several negative environmental experiences and changes in their physical functioning that may be contributing to lowered expectations of self, as well as a resistance to measures that might improve their functioning, are best described by .

Learned helplessness

Explanation:

Learned helplessness  is the process in which a stimuli is obligated to face unpleasant and painful stimuli or situation because it has learned that he/she is helpless.Even though , chances of escaping is present but due to learned behavior stimuli lose expectation of avoiding negative situations.

According to the question,  people who have been exposed to various unpleasant experiences and alteration will not have high hopes regarding resting such situations further as they have learned that escape is not possible.Thus, they are showing learned helplessness behavior.