Question

Which of the following are detritivores? 

1. Earthworms
2. Jellyfish
3. Millipedes
4. Seahorse 
5. Woodlice 

Select the correct answer using the code given below:

(a) 1, 2 and 4 only

(b) 2, 3, 4 and 4 only

(c) 1, 3 and 5 only

(d) 1, 2, 3, 4 and 5

Answer 1

Correct option is (c) 1, 3 and 5 only

Detritivores (e.g., earthworm) break down detritus into smaller particles. This process is called fragmentation. Detritus consists of dead plant remains and dead remains of animals. #1 is wrong. And if earthworm belong to this group then jellyfish (#2) and seahorse (#4) cannot be part of this group. Thus A, B and D are eliminated & we are left with correct Option "C".

Alternatively you could apply some logic that earthworm and woodlice look like insects whereas Jellyfish and seahorses live in sea so 2 and 4 are 'odd men' so eliminate them.