For Scenario 3 what is the correct answer and please explain

For Scenario 3, what is the correct answer and please explain why

when two charged spheres are connected, the charges on them are equally distributed. Now, for Scecario 3:

A and D touched. so, the charges on A and D will be (-Q+0) / 2 = - Q/2 each.

then D and C touched. Then charges on D and C will be (-Q/2 +Q )/2 = Q/4 each.

Then D and A are touched again. So, the charges on A and D now will be (Q/4 -Q/2)/2 = -Q/8 each.

Then A and B are touched. So, charges on A and B are (-Q/8 +0 )/2 = -Q/16

So, the final charges on A = -Q/16, B = -Q/16, C = Q/4, D = -Q/8

Answer will be Q_D=-1/8 Q