Final answer:
The equal-weighted (d) distribution of income refers to the distribution of income according to percentiles.
Step-by-step explanation:
Measuring Income Distribution by Quintiles One common way of measuring income inequality is to rank all households by income, from lowest to highest, and then to divide all households into five groups with equal numbers of people, known as quintiles. This calculation allows for measuring the distribution of income among the five groups compared to the total. The first quintile is the lowest fifth or 20%, the second quintile is the next lowest, and so on. We can measure income inequality by comparing what share of the total income each quintile earns.
Distribution of income according to percentiles, such as the highest 40% or lowest 20%, is known as the equal-weighted distribution of income.