instruction:
You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.
question:
Question: A train passes a station platform in 36 sec and a man standing on the platform in 20 sec. If the speed of the train is 54 km/hr. What is the length of the platform?

Option A: 229

Option B: 240

Option C: 288

Option D: 277

Option E: 221
answer:
Option B

question:
Question: For positive integers x and z, which of the following can be written as z^2?

Option A: x^2+1

Option B: x^2-1

Option C: x^2-24

Option D: x^2+11

Option E: x^2-11
answer:
Option D

question:
Question: There are 12 points in a given plane, no three of which are on the same line. If one of the points is represented as 'A', then how many triangles can be determined with the 12 points that contain the point A?

Option A: 55

Option B: 105

Option C: 182

Option D: 210

Option E: 455
answer:
Option A