An idea most likely to represent “common knowledge” if

An idea can be considered as common knowledge

When all involved in the research or study are aware of the fact and on the same front also know that fact is common and is known to everyone. Also a common knowledge is not cited anywhere and is believed to be easily acceptable. Some  examples of “common knowledge are –  

a)There are 12 months in a year

b)Obama was the president of America

Common knowledge is to know about the general information about anything which is widely known or easily verified. It is nothing unusual, instead, it is the most general knowledge or awareness about a certain statement or evidence which would reliably be accepted by the average educated reader without having to look up. General knowledge can be said as Pyramids are one of the seven wonders of the world and English is the most common language used worldwide.

the form of energy changes and the total energy increases0l

igneous rocks which formed by the crystallization of magma at the surface of the earth called extrusive rocks. they are characterized by fine-grained textures because the rapid cooling at or near the surface did not provide enough time for large crystals to grow.