NBC News projects Trump wins South Carolina GOP primary; U.S. and U.K. conduct airstrikes on Houthi targets in Yemen; Zelenskyy hosts allies as Ukraine marks 2 years since Russian invasion; and more on tonight's broadcast. 

Manhattan D.A. asks for a gag order in Trump's hush money case, Congress is under increasing pressure to prevent a government shutdown, and a new treatment for food allergies shows promise.