Chemistry question structural formula

sorry I did not have an eraser with me so I couldn’t erase my writing but can someone explain in simple terms what the answer should be? Thanks!


In my opinion the answer is A).
K2O ; KCl ; IBr have single bonds
CaS has a double bond BUT it’s ionic not covalent
NO is a weird molecule to draw since it’s an exception to the octet rule, but it has a double bond