I want to know the answer to the following question:
To which two people did Gorbachev grant membership into the Politburo for his own reasons?
All the background I'm provided with is that "On April 23, 1985, Gorbachev brought two protégés, Yegor Ligachev and Nikolai Ryzhkov, into the Politburo as full members.". Is that enough to answer the question?