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.

Q: Question: Find the equation of a line which passes through A(4, -1) and is parallel to x axis.

 Option A: y=-2

 Option B: y=3

 Option C: y=2

 Option D: y=-1

 Option E: y=0

A: Option D
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Q: Question: If |x + 2| = 10, what is the sum of all the possible values of x?

 Option A: -16

 Option B: -13

 Option C: -4

 Option D: -2

 Option E: 12

A: Option C
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Q: Question: A and B together can do a piece of work in 10 days. B alone can finish it in 20 days. In how many days can A alone finish the work ?

 Option A: 20 days

 Option B: 10 days

 Option C: 30 days

 Option D: 40 days

 Option E: 50 days

A:
Option A
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