1 .
The ratio of the age of a father and a son at present is 5: 2. Four years hence the ratio of the ages of the son and his mother will be 1 : 2. What is the ratio of the present ages of the father and the mother?
[ A ]    3 : 4
[ B ]    5 : 4
[ C ]    4 : 3
[ D ]    Cannot be determined
[ E ]    None of these
 Answer : Option D Explanation :