RIF-Reading Is Fundamental. From the article:

10 to 20 billion years ago, the Universe was in an extremely dense and hot (~10 billion °C !) state that exploded in what astronomers call The Big Bang. Eventually, the Universe expanded and cooled and huge collections of gas formed into billions of separate galaxies, and billions of stars formed within each. Many fundamental particles were formed in the beginning of this process, including the basic building blocks of all atoms: protons, neutrons, and electrons. The two lightest elements, hydrogen and helium, were also formed.

...Current models of the Big Bang predict that hydrogen should have been produced three times more abundantly than helium. Indeed, this proportion has been deduced by astronomers in observations of hydrogen and helium in the Universe. ... So how are the heavier elements, such as oxygen, formed? They are synthesized during the evolution of stars.