When people talk about the color of one’s eyes, they are actually talking about the color of the

Iris

Explanation:

Iris is the part of your body whose size never changes from the day we are born to our death.

It function is to allow limited amount of light passes through the lens.

It has pigmented melanin in it  amount of which varies from person to person. When lights reaches the eye, it pass through the fiber of stromal cell and they reflected light from them is in color green, blue, olive, grey.

By this we observe different people have different color eye and  by that we mean different color of iris.

answer: the correct answer is 1.

explanation: there are various process in which a radioactive nuclei decays:

1) alpha decay: in this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. the mass number is reduced by 4 units.

2) electron capture: in this decay process, a parent nuclei absorbs an electron and gets converted into a neutron. simply, a proton and an electron combines together to form a neutron. mass number does not change in this process.

3) gamma ray emission: it is a decay process in which an unstable nuclei gives excess energy by a spontaneous electromagnetic process. this decay releases . this process does not change the mass number.

4) positron emission: it is a type of decay process, in which a proton gets converted to neutron and an electron neutrino. this is also known as -decay. in this the mass number remains same.

from the above information, we see that only alpha-decay is producing a change in the mass number of the nucleus.