Answer:
C. Spindle fibers are pulling the threads apart.
Explanation:
Zygotene is the sub-stage of prophase I of meiosis I, in this stage pairing of homologous chromosomes takes place. The paired chorormosmes are called tetrads or bivalents. In tetrads, a chromatid of one pair is attached to the chromatid in a homologous chromosomes. Crossing over is done between two non-sister chromatids of a homologous pair. After crossing over, homologous chromosomes getting separated in the picture labeled B. Thus, C is the correct option.
