Answer: Option (c) is the correct answer.
Step-by-step explanation:
Metallic character means the level of reactivity of metals. It is known that metals have excess of electrons, therefore, in order to follow octet rule they readily lose electrons to attain stability.
Sodium and potassium are metals and therefore, they have high metallic character.
Whereas silicon is a non-metal and readily reacts with a metal to completely fill its valence shell.
On the other hand, krypton is a noble gas and has completely filled shell. Therefore, it's reactivity will be the least.
Thus, we can conclude that krypton has the least metallic character.