Which of the following is a completely improbable result of a monohybrid cross according to Mendel's experiment?

The Mendelian phenotypic ratio of a monohybrid cross is 3:1, with the dominant trait represented by three and the recessive trait represented by one. Therefore 4 tall plants and 1 medium-height plant, are completely improbable as it is not a part of the Mendelian phenotypic ratio. Additionally, in a monohybrid cross, a tall plant crossed with a dwarf plant will only produce tall or dwarf plants, not medium-height plants, as the blending of traits does not occur in Mendelian genetics.