Yahoo (NASDAQ:YHOO) shares have jumped on news from Dow Jones that Yahoo will say it's exploring "strategic alternatives" in its aftermarket earnings commentary today.<p>Shares were down as much as 4.9% and have leapt to just a 0.4% decline. It's the strongest indication yet that the company will consider a sale of all or part of its Web business.<p>The board has a fiduciary duty to listen to offers, which could come from Verizon (NYSE:VZ) or from private-equity firms that have expressed interest in parts of the business.<p>Sales have fallen at Yahoo in seven of the past 10 quarters.