The beautiful color of corals in the ocean comes from the algae that coexist with them. Zooxanthellae is the most important type of single-celled seaweed. Both take their own needs and want to provide food to each other. Seawater caused by global warming The warming caused a large number of algae such as zooxanthellae to die, which in turn caused the coral itself to die, causing coral reef bleaching. However, research has found that corals can cope with the challenges brought by climate warming by choosing other heat-resistant algae. Which of the following, if true, would weaken this research finding? ? ['Some zooxanthellae can tolerate higher seawater temperatures than other heat-resistant algae.', "The formation of some algae's heat resistance requires a long process.", 'Some zooxanthellae gradually adapted to the rising sea temperature and survived.', 'Dead heat-resistant algae have also been found in some bleached coral reefs.']