Gene regulation during development is which means that

The answer is  hierarchical; genes expressed at each stage control the expressions of genes that act later
Genes that created during development phase act like some sort of bulding block/tempaltes for the formation for various proteins. Later on, Our body will determine which templates/building blocks needed to be produced according to the situation that provided and determine the type of DNa produced

The president's only official legislative duty is to sign or veto bills.