Which elements are found in a high proportion in Earth's crust?

A. aluminum and iron

B. oxygen and silicon

C. calcium and sodium

D. potassium and magnesium

I think its calcium and sodium I'm not sure

Basically, this is a tricky question. And it has more than one answer. The elements that are found in a high proportion in Earth's crust are oxygen, aluminium, iron, calcium, potassium, sodium, and magnesium. But for your Option, I think it is B) Oxygen and Silicon. This is because Oxygen makes 46.6% while Silicon makes 27.7% of the Earth crust. They are like the highest.