Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.

[EX Q]: Problem: if an investor puts $ 800 in a savings account that earns 10 percent annual interest compounded semiannually, how much money will be in the account after one year ?
Options: a. $ 878, b. $ 880, c. $ 882, d. $ 884, e. $ 886
[EX A]: c

[EX Q]: Problem: what least number should be added to 1057, so that the sum is completely divisible by 23
Options: a. a. 4, b. b. 1, c. c. 2, d. d. 3, e. e. 5
[EX A]: b

[EX Q]: Problem: after successive discounts of 20 %, 10 % and 5 % a certain good is sold for rs. 6700. find the actual price of the good.
Options: a. s. 6000, b. s. 9000, c. s. 10800, d. s. 9795, e. s. 9980
[EX A]:
d