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: A sum of Rs.4800 is invested at a compound interest for three years, the rate of interest being 10% p.a., 20% p.a. and 25% p.a. for the 1st, 2nd and the 3rd years respectively. Find the interest received at the end of the three years?

Option A: Rs.3129

Option B: Rs.3120

Option C: Rs.3108

Option D: Rs.3106

Option E: Rs.3127
[A]: Option B

[Q]: Question: The amount of an investment will double in approximately 70/ p years, where p is the percent interest, compounded annually. If Thelma invests $ 60,000 in a long-term CD that pays 5 percent interest, compounded annually, what will be the approximate total value of the investment when Thelma is ready to retire 42 years later?

Option A: $ 280,000

Option B: $ 320,000

Option C: $ 360,000

Option D: $ 480,000

Option E: $ 540,000
[A]: Option D

[Q]: Question: John purchased a fridge & a mobile for Rs. 15000&Rs. 8000 respectively. He sold the fridgeat a loss of 4% and the mobile phone at a profit of 10%. Overall how much he make a profit.

Option A: Rs. 100

Option B: Rs. 150

Option C: Rs. 200

Option D: Rs. 300

Option E: Rs. 350
[A]:
Option C