What are the advantages of having proof before you make any conclusion about your own understanding for scientific method?

Helps in accepting and defending the conclusion.

Explanation:

The main advantages of having proof before you make any conclusion is that it gives a reason for accepting the answer given by you because you have the proof to prove your answer so no one questions on your answer. The proof give you strength to defend your conclusion and make your conclusion right in front of the world. Without proof no one can accept your answer because every answer of a scientific question wants a proof for its validation.

answer is: nuclear fusion produces elements that are heavier than helium.

nuclei combine to form a heavier nucleus, releasing energy.  

for example, fusion of hydrogen atoms at the sun.  

this fusion nuclear reaction is in the inner core of the sun and hydrogen (atomic number 1) is conveted into helium (atomic number 2).  

the inner core is the central region of the sun and all solar energy is produced in the core by nuclear fusion.