Final answer:
None of the given sets of elements have atomic numbers that add up to 200.
Step-by-step explanation:
The elements in a set are valid if their atomic numbers add up to 200. Based on the given options, the set of elements that satisfy this condition is d) Iron, Cobalt, Nickel.
To determine if the elements in this set add up to 200, we need to find the atomic numbers of each element and sum them. Iron has an atomic number of 26, Cobalt has an atomic number of 27, and Nickel has an atomic number of 28. Summing these atomic numbers, we get 26 + 27 + 28 = 81. Since the sum is less than 200, this set of elements is not valid.
Therefore, none of the given options are valid sets of elements with atomic numbers that add up to 200.