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: Look at this series: 8, 43, 11, 41, __, 39, 17, ... What number should fill in the blank?

 Option A: 22

 Option B: 33

 Option C: 14

 Option D: 16

 Option E: 18
[EX A]: Option C

[EX Q]: Question: Twelve participants are participating in a competition. In how many ways can the first three prizes be won?

 Option A: 1320

 Option B: 680

 Option C: 820

 Option D: 720

 Option E: 620
[EX A]: Option A

[EX Q]: Question: There are a lot of houses such that the numbers of their doorplates are odd numbers and the first number of the doorplates is 545, the last number of the doorplates is 855. How many houses are there?

 Option A: 155

 Option B: 161

 Option C: 154

 Option D: 156

 Option E: 158
[EX A]:
Option D