LONDON—The inflation genie is finally out of its bottle. Now investors are waiting to see whether the European Central Bank (ECB) on Thursday admits that price pressures are too significant to ignore. They will also want an explanation of what that means for its ultra-easy policy stance. Big decisions on the future of the ECB’s pandemic emergency stimulus will wait until December. But with surging energy prices and supply bottlenecks, Thursday’s meeting should be anything but dull. Here are five key questions on the radar for markets. 1. What Does High Inflation Mean for the Policy Outlook? The ECB may acknowledge that a jump in price pressures is likely to last longer than anticipated, but the central bank is unlikely to abandon its dovish policy stance just yet. Its 2023 inflation forecast is 1.5 percent, below the 2 percent target, and policymakers argue that tightening policy too early could hurt …