Which among the following is the second trophic level in a lake ?

Zooplankton

The correct answer is Option (1) – Zooplankton

Trophic levels represent the positions that organisms occupy in a food chain. Here's a breakdown of the trophic levels in lake :

Phytoplankton: These are primary producers (first trophic level) that perform photosynthesis to produce energy from sunlight.

Zooplankton: These are primary consumers (second trophic level) that feed on phytoplankton.

Fishes: These can occupy various trophic levels depending on their diet. Many small fish that feed on zooplankton are secondary consumers (third trophic level), while larger predatory fish can be tertiary consumers.

Shark: Typically found in marine environments, sharks are apex predators and usually occupy the higher trophic levels (fourth or fifth).

In a lake ecosystem, the second trophic level is occupied by zooplankton, which feed on the primary producers (phytoplankton).