Final answer:
The correct answer is that a rich country tends to have more than ten times the income of a poor country and typically has a longer life expectancy.
Step-by-step explanation:
The relationship between income levels and factors such as life expectancy is complex and varies across different countries. High-income countries typically exhibit significantly higher standards of living and longer life expectancies than low-income countries. Such countries often benefit from better healthcare, education, and access to resources such as clean water and reliable infrastructure. However, rapid economic growth in some low- and middle-income countries has led to substantial improvements in living standards and a narrowing income gap when compared to richer countries. Despite this growth, there is still a clear discrepancy in life expectancy rates, with high-income countries generally having a longer life expectancy. Therefore, the correct answer in the context provided would likely be that a rich country has more than ten times the income of a poor country and also generally enjoys a longer life expectancy (option c).