Tsugi no Itte
Tsugi no itte in Japanese literally means the one next move. By implication it refers to the best move . Many problems are published as tsugi no itte problems in magazines, pamphlets, and books. Often they are multiple choice problems. As you might expect, these popular problems do not require much reading to solve.
It is not a synonym for Kono itte (the only move): Tsugi no itte is a type of problem. Kono itte is a description of a move as the only move. For instance, you would never see a commentary saying a particular move was tsugi no itte. It would say it is kono itte.