**Core Concept**
Movement across socioeconomic levels refers to the process by which individuals or families change their social and economic status, transitioning from a lower to a higher or vice versa. This concept is essential in understanding health disparities and the impact of socioeconomic factors on health outcomes.

**Why the Correct Answer is Right**
The correct answer is related to the concept of social mobility, which involves the movement of individuals or groups up or down the social ladder. This can occur due to various factors such as education, occupation, income, and access to resources. Social mobility can be influenced by individual efforts, social policies, and structural factors like poverty, racism, and sexism. Theories of social mobility, such as the "American Dream" hypothesis, suggest that individuals can improve their socioeconomic status through hard work and determination.

**Why Each Wrong Option is Incorrect**
**Option A:** This option might refer to social stratification, which is the process of creating a hierarchy of social classes. While related to social mobility, social stratification is a broader concept that refers to the structure of social inequality, rather than the movement of individuals across socioeconomic levels.

**Option B:** This option might refer to social change, which is a broader concept that encompasses various forms of social transformation, including changes in social norms, values, and institutions. While social change can lead to social mobility, the two concepts are not synonymous.

**Option C:** This option might refer to social status, which is a person's position within a social hierarchy. While social status can influence social mobility, the two concepts are distinct.

**Clinical Pearl / High-Yield Fact**
A key factor influencing social mobility is access to quality education, which can provide individuals with the skills, knowledge, and networks necessary to improve their socioeconomic status.

**Correct Answer:** D.