First Auction Power Plant in Power Grid?
After D won the first auction, Player A is obligated to choose a plant again. You may have missed this on page 3 of the rules:


  When the auctioning player wins the auction and gets the power plant, the next player in turn order takes his turn at offering a power plant for auction, if he has not already purchased a power plant this round. If he has, the next player in turn order may start an auction, and so on. When a player other than the player who started the auction wins the auction, the auctioning player may choose a new plant to auction from the actual market or pass.


Since the exception says everyone must buy a power plant first round, Player A may not pass.