## Core Concept
The Physical Quality of Life Index (PQLI) is an attempt to measure the quality of life or well-being of a country. It is a composite index that averages three basic indicators: literacy rate, infant mortality rate, and life expectancy at age one.

## Why the Correct Answer is Right
The PQLI is specifically designed to provide a more accurate representation of a country's well-being by focusing on these three key areas. Literacy rate reflects the educational attainment, infant mortality rate indicates the health care quality and its accessibility, and life expectancy at age one assesses the overall survival and health conditions. These indicators are directly related to the physical aspects of quality of life.

## Why Each Wrong Option is Incorrect
- **Option A:** Literacy rate is one of the indicators of PQLI, reflecting the educational component of quality of life.
- **Option B:** Infant mortality rate is another indicator, signifying the healthcare and nutritional status of a population.
- **Option C:** Life expectancy at age one is also an indicator, representing the health and survival chances of a population beyond infancy.

## Why Option D is Correct (Implicit)
Since the question asks for an exception and given that literacy rate, infant mortality rate, and life expectancy at age one are all components of PQLI, any option not listed among A, B, or C would be correct if it doesn't belong. However, without explicit details on option D, we infer based on the process of elimination and understanding of PQLI components.

## Clinical Pearl / High-Yield Fact
A key point to remember is that the PQLI does not directly account for GDP or income per capita, focusing instead on basic physical needs and outcomes. This makes it distinct from other indices like the Human Development Index (HDI), which includes GDP per capita.

## Correct Answer: D.