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.

[EX Q]: Question: If the charge of staying in a student youth hostel $18.00/day for the first week, and $15.00/day for each additional week, How much does it cost to stay for 23 days?

 Option A: $336

 Option B: $289

 Option C: $282

 Option D: $274

 Option E: $286
[EX A]: Option A

[EX Q]: Question: (3x + 1) (2x - 5) = ax^2 + kx + n . What is the value of a - n + k ?

 Option A: 5

 Option B: 8

 Option C: 9

 Option D: 14

 Option E: 11
[EX A]: Option D

[EX Q]: Question: A person walking at 4 Kmph reaches his office 8 minutes late. If he walks at 6 Kmph, he reaches there 12 minutes earlier. How far is the office from his house?

 Option A: 4 1/5 Km

 Option B: 4 1/7 Km

 Option C: 3 1/5 Km

 Option D: 3 1/7 Km

 Option E: 4 Km
[EX A]:
Option E