Unknown element x has four energy levels, five valence electrons, and is a metalloid. what is elements x?

a-Si

b-Se

c-Ge

d-As

Element X is Arsenic (As)

Explanation:

Elements in the periodic table are either metals, non-metals or metalloids. Metals are elements that react by losing electrons to obtain a stable configuration and form cation. Non-metals are those elements that react by gaining electrons to form a stable configuration and form anion. Metalloids are elements in the periodic table that have both metallic and non-metallic properties. Examples of metalloids include Selenium, Arsenic, Boron, etc. Arsenic is a metalloid in period 4 (four energy levels) with five valence electrons.