The correct answer is option D, tetrad
Tetrad consist of two homologous chromosomes resulting into a foursome of DNA formed during meiosis. The 46 chromosomes in humans replicate during the process of meiosis. The original chromosomes and the replicated chromosome get attached to form conjoined twins, known as sister chromatids. During the prophase of meiosis, a four - part structure is formed which consists of two homologous chromosomes with two sister chromatids in each chromosomes.