At what point can I stop and freeze my samples when using ChIP?

There are several points at which the procedure may be put on hold.

A) After pelleting cells following formaldehyde fixation and washes, you can freeze the cell pellet at -80°C.

B) After making the lysate, you can freeze the lysate at -80°C.

C) After sonication, you can store the chromatin in aliquot and store at -80° C.

D) After DNA isolation prior to DNA purification, you may store DNA at -20°C or 4°C.