Answer:
Na and K
Explanation:
Every elements in the same group have similar chemical characteristics
<span>The challenge of reproducing is one of important manners which distinguishes migratory birds from another birds. The question is that which examples descrbe such manners, and for that, we can choose A, C and D</span>
The goal is to selectively develop specific desired characteristics in plants or animals, eventually creating the desired offspring.
Liver cells because it uses the most energy than the other choices
