Explanation:

- Poverty line: A common term used to measure poverty by setting a specific income or consumption threshold. People below this line are considered impoverished.

- Correct answer

- Vulnerability: Refers to the susceptibility of individuals or groups to fall into poverty due to external shocks, lacks measurement based on income or consumption.

- Social exclusion: Describes a process affecting people’s ability to participate fully in society, not directly a measure of poverty.

- Poverty estimates: Refers to calculations made based on data to understand the extent or dimensions of poverty, not a direct measure.