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.
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Question: Question: What is the units digit of 18! + 5 ?

 Option A: 2

 Option B: 3

 Option C: 4

 Option D: 5

 Option E: 6

Answer: Option D


Question: Question: A sequence contains y numbers of alternating positive and negative numbers, If the first number is postive and y is an even number, how many negative numbers are in it?

 Option A: (y+1

 Option B: (y-1

 Option C: y/(2+1

 Option D: y/(2-1

 Option E: y/2

Answer: Option E


Question: Question: If f(x)= 2x^2- 3x+5 and g(y)= 2y-4, then g(f(x))

 Option A: 7x^2+45x+9

 Option B: 9x^2-15x+4

 Option C: 4x^2-6x+6

 Option D: 8x^2-9x+6

 Option E: 9x^2+79x+78

Answer:
Option C