This is a minute cell which separates from the animal egg during maturation is known as

The correct option is polar bodies.

During the process of oogenesis (the formation and maturation of female gametes or eggs), cell division is unequal. This process begins with a primary oocyte, which undergoes meiosis I to produce a large secondary oocyte and a tiny cell containing very little cytoplasm. This small, minute cell is called the first polar body.
Subsequently, the secondary oocyte undergoes meiosis II, resulting in a large mature egg cell (ootid or ovum) and a second tiny cell, the second polar body.

The primary function of these unequal divisions is to conserve as much of the nutrient-rich cytoplasm as possible in a single mature egg cell to sustain the potential embryo after fertilization, while still reducing the chromosome number by half. The minute cells that separate and contain minimal cytoplasm are called polar bodies, and they eventually degenerate.