The 'Middle-Income Trap' refers to ____________.

The correct option is: Struggle to attain high income status.

The term "Middle-Income Trap" is an economic concept that describes a situation where a developing nation manages to transition from a low-income to a middle-income level (often driven by cheap labor and basic industrialization) but subsequently gets stuck at that level.
In this phase, the country struggles to compete with low-income, low-wage economies in cheap manufacturing, while simultaneously lacking the advanced technology, innovation, and high-value-added service industries required to compete with high-income, developed economies.

As a result, economic growth stagnates, and the nation faces a prolonged struggle to make the final leap and attain high-income status.