From the given option, 12 is the only option which when reduced by 4 gives 8 as a perfect cube and when 12 is increased by 4 gives 16 which is a perfect square. If she waits for 14 more years, then her age would be 25 a year ago, which is the square of 5. Also, she will be 27 years old the next year, which is the cube of 3