The correct option is B Recombinations
Crossing over is the process which occurs in meiosis I. The genetic material gets exchanged between the non-sister chromatids of the two homologous chromosomes which are obtained as one from the mother (maternal) and one from the father (paternal). The genetic exchange is responsible for the variation in the genetic composition of the offspring due to recombination. The recombination helps in bringing variation and contributes towards evolution. Thus, the correct answer is option B.