Answer:
It can be inferred that the wrinkled pea trait is a dominant trait. This is because when a pea plant with wrinkled peas (which would be homozygous recessive) is crossed with a pea plant with smooth peas (which would be homozygous dominant), all of the offspring having wrinkled peas indicates that the offspring have inherited at least one dominant smooth pea allele, but still exhibit the wrinkled phenotype. This suggests that the wrinkled pea trait is dominant over the smooth pea trait.