Which grid will replace the question mark?

In this kind of black-and-white grid series, two independent rules run in parallel: the total number of filled circles rises by a constant step from one grid to the next, and a small set of marked positions -- a growing corner cluster plus one lone inner dot -- each cycle through fixed spots in a set one-way rotation. The missing grid is found by extending both the running count and the rotation by exactly one further step.

1. Count the filled circles in each given grid in order: 3, 4, 5, 6, then 7 -- the total rises by exactly one circle at every step.

2. Extending that run (3, 4, 5, 6, 7) by the same step of one gives the total the missing grid must have: 8.

3. Separately, track the single dot that sits apart from the fixed centre dot and the corner cluster: across the given grids it occupies one inner corner, then the next, then the next, moving one step clockwise around the four inner corners each time and never repeating a corner out of turn.

4. Continuing that one-way clockwise rotation by one more step after its most recent position gives the inner corner that the missing grid's lone dot must occupy.

5. Also track the larger cluster of circles anchored at a true corner of the grid: after every full circuit around the four corners it grows by one circle (from a two-dot cluster to a three-dot cluster); the missing grid continues that same clockwise handover to the next corner in line, now as a three-dot group.

Checking which option satisfies all three requirements together -- eight filled circles, the inner dot advanced exactly one step further around its rotation, and the corner cluster handed on to the next corner as a three-dot group -- gives a single consistent match; every other option breaks at least one of the three rules (the count, the inner-dot rotation, or the corner-cluster handover).

Grid B is the figure that satisfies every rule at once, so it replaces the question mark.