MCF's COMMON 12

If it’s Thursday, then it must be time for MCF's COMMON! And I know, by the time you see this, it will technically be Friday. For me, it’s Thursday night, it’s been a long week, and though it was a pretty good one, I’m ready for the weekend. One more day, after this one game. If you don’t know how to play, now you’ll know:

Below I'm going to list FIVE groups of FOUR things. Each group has some thing in common, some thing that links each quartet. It's up to you to guess, and I'll reveal the answers tomorrow.

20 items. 5 COMMON bonds. Through a combination of skill, luck, knowledge, and flat out guessing, can you guess what they are?

GROUP 1
(A) Umlaut.
(B) Grave.
(C) Acute.
(D) Circumflex.

GROUP 2
(A) Üter.
(B) Dolph.
(C) Martin.
(D) Wendell.

GROUP 3
(A) Spike.
(B) Eric.
(C) Lestat.
(D) David.

GROUP 4
(A) Techno.
(B) Tele.
(C) Strato.
(D) SAW.

GROUP 5
(A) .
(B) ,
(C) -
(D) )