Cereals are usually fortified with three most common minerals and vitamins which are:
1- Iron
2- Vitamin D
3- Vitamin B-12
Comparing the above to the given choices, we will find that the best answer is:
b. iron
The threshhold for gamma rays is between 1 * 10^17 Hz and 9*10^17 Hz
Since this question goes much beyond that the answer is you much be working with a gamma ray. It is "Best" classified this way because nothing else will fit. The others are all much lower.
Kinetic energy is the energy of a moving object. Usually it is numericallydefined for an object as KE = 0.5*m*v^2