Task: Question Answering
Input (English): Problem: the ratio , by volume , of bleach ( b ) to detergent ( d ) to water in a certain solution is 2 : 40 : 100 . the solution will be altered so that the ratio of bleach to detergent is tripled while the ratio of detergent to water is halved . if the altered solution will contain 300 liters of water , how many liters of detergent will it contain ? 
Options: ['a ) 60', 'b ) 50', 'c ) 40', 'd ) 80', 'e ) 70']
Output (English): a