Final answer:
The cleavage furrow is the structure that forms near the cell's equator during cytokinesis, as opposed to the centrosome which gives rise to mitotic spindles. option A.
Step-by-step explanation:
As the cell undergoes cytokinesis, the structure that forms near the cell's equator is called the cleavage furrow. This cleavage furrow is a contractile band made up of microfilaments that forms around the midline of the cell during cytokinesis.
The actin filaments within this structure pull the equator of the cell inward, forming a fissure that deepens as the actin ring contracts, leading to the division of the cell into two separate cells.
In contrast, the mitotic spindles, which play a critical role during cell division, arise from the centrosome. This is not to be confused with the centromere, which is the region where sister chromatids are attached, nor the kinetochore, which is a structure on the centromere where spindles attach.
The cleavage furrow is distinct from these components and is involved specifically in the physical process of cell division. Option A,