Answer:
None of these
Explanation:
start of w/ a ratio of 4:7.
18 cannot increase by a factor of 4 so the first answer is incorrect.
14 cannot increase by a factor of 4 so the second answer is incorrect.
16 can increase by a factor of 4 and 49 can increase by 7 as well, however this is still the wrong answer. So, go step by step and increase the first value by 4, and the second value by 7.
4:7-> 8:14-> 12:21-> 16:28
This ratio does not equal to 16:49, so therefore, none of these is the correct answer.