Luchins conducted a classic study using the water jug problem, in which subjects got several consecutive problems in a row that required a B - A - 2C solution. What did he find? Group of answer choices Subjects persisted in trying to use the B - A - 2C solution even when a shorter solution was available. On a problem in which the B - A - 2C solution wouldn't work (but a shorter solution would work), subjects believed the problem couldn't be solved. All of the answers shown here are correct. Subjects showed a mental set