Marcel Duchamp was the first to call the works of Alexander Calder mobiles true or false?

False. Marcel Duchamp did not coin the term "mobiles" for Alexander Calder's kinetic sculptures. The term is attributed to Duchamp in reference to Calder's work, but it was actually Calder himself who first used the term. Duchamp recognized and praised Calder's innovative art, but he was not the originator of the term.