Is the first step in development of all multicelled organisms

The first step in the development of a complex organism is the establishment of a pattern of cells with different states that can differentiate along different pathways. … [P]atterning processes require signalling between and within cells, leading ultimately to gene activation or inactivation. Such a process can lead to reliable patterns of cell activities only if all the cells have the same set of genes and obey the same rules [

Being composed of one or more cells

Hey there, for asking a question here.  the postovulatory phase  of the ovarian cycle leaves the leftover follicle, from which the ovum was released, develop into the corpus luteum.answer: letter a  ✅hope that ! ★ if you have further questions about this question or need more , feel free to comment below or post another question and send the link to me. -unicornfudge aka qamar