Which set of ionization energy (IE) data represents an atom that has one electron in its outermost electron shell? (My friend, teacher, and I can't conclude on the answer.)

[lolkeinthatsghey]

My friend and I were reviewing over ionization energies when we stumbled upon this beauty. 

(Spoiler reveals our opinion, I wouldn't want you to be influenced by our opinion!

Spoiler

We think that the answer is B or D because there is a large jump from the 1st to 2nd IE; thus, eliminating A and C. However we became stuck on the next IE levels. I've asked my teacher her opinion on the answer, and she also struggled to choose from B or D.

What is your opinion on this?

 

[kw0573]

1. Alkali metals (Li and others) have one electron in outer-most shell. 
2. Ionization energy is directly proportional to how difficult it is to remove an electron. We know that atoms want to get to a full octet in outer most shell, so the the alkali metals have lowest first ionization energy (not at all difficult), whereas noble gases have highest first IE. This means the biggest jump is between 1st and 2nd IEs. This is shown by IE of Li
3. Choices and the biggest jumps:
A-between 2nd and 3rd.
B-between 1st and 2nd.
C-between 2nd and 3rd.
D-between 1st and 2nd.

4. Note that in all elements Li to Ne, the largest jump is at least 5 times from isoelectric to alkali metals to isoelectric to noble gases (115,380 > 5 * 23,070). However this is not case for D, from 854 to 1981. You see many of these energy doubling in 1st/2nd from Be to F. The best and the only answer, is B (despite only a 4 times difference).