What elements in the building block for all other elements

Chlorine, oxygen, silicon, aluminum, iron, calcium, sodium, potassium, magnesium, hydrogen, phosphorous and carbon make up over 99 percent of the earth's crust, atmosphere and oceans (by weight). These elements are truly "building blocks"—they combine with other elements to form our world.

Of the 92 natural elements, 25 are essential for life. There are six main elements that are the fundamental building blocks of life. They are, in order of least to most common: sulfur, phosphorous, oxygen, nitrogen, carbon, and hydrogen.

the number of protons in the nucleus of a given element. has slight luster and conducts electricity at high temperatures like metal.but like a nonmetal,boron is brittle and does not conduct electricity well at low temperatures. in graphite, carbon is a soft,brittle solid.it is reflective,ductile,or malleable.

the answer to your question is c