Answer:
D. reproduction
Explanation:
If the species doesn't reproduce they die out or become extinct.
An example of this is to whether smoke cigarette or not. People smoke whenever they feel anxious with their activities but they were thinking that it is not a habit, but in the end, they will be used to it that is why they tend to forget how to live without smoking. This is the reason why they got addicted and to some serious problems with their health.
Answer:
The answer should be
NaI→2Na+I2. :)
