(a) The population of tiger increases

(b) The population of grass decreases

(c) Tiger will start eating grass

(d) The population of tiger decreases and the population of grass increases

Correct option – ( d )

Explanation for correct option – if in the food chain deer is missing then the number of tiger will decrease as there will be nothing available for them to feed on , similarly the grass increases as there is no one to eat them up .

Hence correct option is The population of tiger decreases and the population of grass increases