What is the most logical next event?

There's a lady doing a tutorial on how to make a cotton soft ogura cake. She begins by mixing the ingredients in a large bowl placed on her kitchen counter. she

Pick from: I. then uses a cookie cutter to cut the cake and measures out just the creme swirl.; II. then oranges and mangos and lemons are added and blended together in a circular shape.; III. then fills the bowl with baking soda and in the end lets her baking powder and sugar out.; IV. adds some eggs to the flour along with vanilla essence.;
IV.