What are the lake levels/zones, starting from the top layer?

The correct answer is based on the structure of stratification found in stratified lakes. The zones are defined by their temperature gradients and biological activity. The epilimnion is the uppermost layer, characterized by warmer temperatures and significant sunlight penetration, which supports photosynthesis and a vibrant ecosystem.

Beneath the epilimnion lies the thermocline, which serves as a transitional layer where temperature changes rapidly with depth. This zone typically acts as a barrier to mixing between the warmer upper waters and the cooler deeper waters.

The hypolimnion is the lowest layer of the lake, where temperatures are colder and typically more stable throughout the year. This area usually has lower biological activity compared to the layers above it, primarily due to reduced light availability and lower temperatures.

Thus, the correct sequence of layers in a stratified lake from top to bottom is epilimnion, thermocline, and hypolimnion. Understanding this order is essential for water quality management, fish habitats, and ecological studies.