Which one of the following types of organisms occupy more than one trophic level in a pond ecosystem.
1. Frog
2. Phytoplankton
3. Fish
4. Zooplankton

Identify the possible link "A" in the following food chain :    
Plant → insect - frog → "A" → Eagle
1. Rabbit
2. WoIf
3. Cobra
4. Parrot

Identify the likely organisms (a), (b), (c) and (d) in the food web shown below:     

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