White to move
1. Material: White is up a pawn, that is about to Queen. But White cannot defend it.
2. King safety. White’s King is pinned to the light squared bishop. Black’s King is in no immediate danger.
3. Activity: Black’s rook is more active, and his bishop is not pinned like White’s.
4. Pawn structure. White has the better pawn structure on the Kingside, and has a passed pawn on the Qside.
Biggest threat for White is 1…Rxa7 losing the passed pawn and heading into a draw.
Problem is that White cannot defend the pawn with the rook since the rook is lost with either 1.Ra8 or 1.Rc7.
Candidates:
Highlight text for answer:
1. Rxc6+ {the most forcing move} Kxc6 2.a8=Q Rxa8 3.Be4+ {Wins the Black rook due to the skewering of the King and the Rook}