C. Sodium and potassium are in the same chemical family.
Chemical family in a periodic table is a column of elements which share some similar physical or chemical properties. For example, the elements of group one are mostly soft metallic solids and they share similar metallic properties. The topmost element in a group is used to identify the group.
A tabular arrangement used to classify elements which are placed horizontally by means of atomic number and vertically by their properties.
The given element belongs to alkali metals which have low density, highly reactive, and have low electronegativity.
Potassium is a chemical element with the symbol K and atomic number 19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure.
