Answer:
Noble gases, atoms which have complete filled outer orbits.
Explanation:
SInce, you have given no options elements like Neon, Helium,etc
Answer:
I would think C because you dont want to sell it (A), you dont want to conduct it or launch it agai, (B or D), so you would redesign it to make it better.
When alpha decay takes place, two protons and two neutrons are forcefully ejected from the nucleus in a way that looks very similar to a Helium nucleus. This type of decay causes the atomic mass of the parent particle to drop by four (four particles lost), but the atomic number drops by only two (two protons lost). Therefore, your answer is C.
The answer would be C. Pb
