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: If x < y < 0, which of the following must be true?

 Option A: 2xy/3x is a negative integer

 Option B: x-y is a positive integer

 Option C: (-x

 Option D: x/y is a negative integer

 Option E: 2x+y is a negative integer
Option C

Question: If a man crosses a 600 m long street in 5 minutes. What is his speed?

 Option A: 7 km/hr

 Option B: 7.1 km/hr

 Option C: 7.2 km/hr

 Option D: 8 km/hr

 Option E: 8.5 km/hr
Option C

Question: The greatest number of four digits which is divisible by 15, 25, 40 and 75 is:

 Option A: 9000

 Option B: 9400

 Option C: 9600

 Option D: 9670

 Option E: 9800

Option C