Answer:
Option A.
Step-by-step explanation:
We will check each option given in the question.
Option A. If an elephant walks with the speed = 15 steps a minute
If it takes x hours to cover 570 steps then the expression should be
15x = 570
Therefore, Option A. will be the answer.
Option B. A giraffe eats leaves = 570 per hour
If it eats for 15 hours then number of leaves eaten by giraffe = 570×15
So the expression is not formed.
Therefore, Option B is not the answer.
Option C. Dandelions eaten by the donkey = 15
and dandelions eaten by cow = 570
So total dandelions eaten by cow and donkey together = 15 + 570
Again the expression is different so Option C is incorrect
Option D. A Canary flew for 15 hours towards north, then turned east and flew for 38 hours.
Here speed of the canary is not mentioned so it's not possible to form any expression for the distance covered by the canary.
Therefore, Option D is also incorrect.
Option A. is the answer.