Which of the following scenarios represents a bottom-up approach to problem-solving?

mowing the lawn by dividing the lawn into sections and taking breaks in between

a small child learning the letters of the alphabet, then learning how to sound out words, and eventually working up to reading comprehension

deciding to make a cake and then making a list of the ingredients to purchase

planning a goal of exercising 30 minutes a day

a small child learning the letters of the alphabet, then learning how to sound out words, and eventually working up to reading comprehension