The grey crescent area is present:

Explanation

The grey crescent is a characteristic feature that appears in the fertilized egg of amphibians during a process called cortical rotation. After sperm entry, the cortex of the egg rotates relative to the inner contents of the egg, creating a distinctive crescent-shaped region with a different appearance, often appearing "grey" or lighter in color.The formation of the grey crescent is significant in amphibian development. It marks the establishment of the dorsal-ventral (back-belly) axis, which is crucial for the subsequent development of the embryo. It plays a role in organizing and patterning the embryonic tissues.The grey crescent is essential for the process of gastrulation, during which the single-layered blastula is transformed into a multi-layered structure known as the gastrula. This transformation is a key step in embryonic development and results in the formation of the three primary germ layers: ectoderm, mesoderm, and endoderm.