It IS NOT A because after a fire, soil remains, so it would be secondary, not primary. D is INCORRECT because after a volcano, only rock is left so it is primary succession, not secondary.
If you can post the picture I could tell you the correct answer.
"Connective",
Hope this helped :)
The answer is C. Atomic Number
Answer:
The correct answer is - 2. Helium.
Explanation:
Nuclear fusion is a reaction that involves the fusion of two or more atomic nuclei to make different atomic nuclei with subatomic particles and releases a huge amount of energy.
Two hydrogen molecules with one proton and one neutron fused together to make a larger helium molecule with two protons and two neutrons and release a huge amount of energy.
1H^2+1H^2 ====> 2He^4 + energy
