I am never doing a quiz giveaway again. I understand your pain now. This stuff is like torture.

It's simple - their mum is a slut!

They all pulled their heads out of their asses xD

Hmm quizzes eh

Lol, this is what I was thinking of when I wrote my answer!

These are better answers than before.

They are related by your post? O_o

Got it:

what relates a man (we will just refer to him as 'he') to four people with a different hair colour.

Maybe the "man" and the four people are siblings, and their parents had heterozygous genes or something? Biology I, don't fail me now!

a relationship

that was the question - what's the answer...

They all share one parent.

The answer is penis! Always bet on penis! ;)

I can only think of two relations that naturally come in fours, grandparents and parents/parents-in-law. The four could easily have different hair colors, and I suppose through a quirk of genetics the man could come out with a fifth (through some seriously recessive genes).

There's been too much penis inthis thread today as it is!