Scientists in Scotland Figured Out a Novel Method to Clone

Scientists in Scotland figured out a novel method to clone animals successfully.It involved

A) using an egg and a nucleus that were at the same stage of the cell cycle.
B) using an egg that was in cytokinesis and a nucleus that was in S stage of the cell cycle.
C) using an egg that was cleared of mitochondrial DNA (mDNA) .
D) using gp120 attachment proteins to facilitate cell fusion.