Answer:
A is a solid. C is a gas. In solid an liquid the particals are touching. In C, the particals have less affect on each other because they are so far apart.
Here in nuclear reaction we can say that sum of neutrons and protons in reactant side and product side will be same always
Here mass number on the product side is given to us
so sum of mass number is given as
now on the reactant side also the number must be same
now we will have
Now number of protons on product side is given as
now we also know that atomic number of Fe is 26
so now we will have
now the equation is given as
If the answer is not C D then is A bc of the way it crosses over