Q.

What will happen if deer is missing in the food chain given below

Grass  Deer  Tiger

1 The population of tiger increases.  
2 Tiger will start eating grass.  
3 The population of grass decreases.  
4 The population of tiger decreases and the population of grass increases.  

Ans.

(4)

The tiger is a secondary consumer which eats deer. If the deer is missing, there will be no food for the tiger. So, if deers are missing, the population of grass will increase.