Final answer:
In William Golding's 'Lord of the Flies', it is Ralph who places the highest importance on building shelters for protection and security.
Step-by-step explanation:
The character who says that shelters are the most important thing that need to be made, rather than fires, is Ralph. In William Golding's novel 'Lord of the Flies', Ralph emphasizes the need for shelters as a means of providing security and protection from the elements. His perspective often comes in contrast to Jack's priorities, which include the importance of hunting and the excitement of creating fires.