Final answer:
Optimism is the option most strongly associated with mental health, as it contributes to positive health outcomes and aids in effective coping strategies.
Step-by-step explanation:
The element that is most strongly associated with mental health out of the options provided is B. optimism. Studies have shown that optimism, which is a general expectation that good things will happen, is linked to a variety of positive health outcomes including better mental health, coping strategies, and even physical well-being. In contrast, isolation often has a negative impact on mental health, increasing the risk of conditions such as depression and anxiety. Intelligence and self-employment are not as directly associated with mental health as optimism is.