The accepted model of the atom was changed.
Answer:
Explanation: First one is Purple, purple, White.
Hairy, Hairy, Non hairy.
The cyanide is

A carbon atom has 4 valance electrons and nitrogen has 5. Below is a Lewis-dot-structure of cyanide.
:N≡C.
The carbon atom is still one electron short of having a full octet and so it will seize another electron from almost anything, making the cyanide ion negative and whatever it took the electron from it now positive.
Letter D.
The scarier the better, and many people like loops