BP PLC is writing down as much as $17.5 billion of its assets and might leave some of its oil and gas in the ground because of lower energy prices and weakened demand amid the global crisis caused by the novel coronavirus. The British energy giant sees the pandemic—which caused nationwide shutdowns and drove U.S. oil prices into negative territory—having a lasting economic impact, leading to fragile energy demand and sinking prices. The virus will also accelerate the world’s shift to a lower-carbon economy, BP said,…