The logic followed is: i) Rajkiran starts walking from his home and goes 480 m towards the south. ii) Then he turns right and walks 165 m. iii) He again turns right and walks 210 m. iv) He finally turns left and walks 120 m to reach a garden. The diagram for the given information is as follows:
Now, the office of Rajikran is 270m south of his home. And it can be seen that the distance between Garden and his office is 165 + 120 = 285m. Hence, the correct answer is "285 m".