In Chapter 5, Ralph says the most important thing is a)keeping the fire going
b)staying civilized
c)getting some meat
d)having fun

a question like this requires the excerpt to be included in order to answer the question.

there is a sequence and logical steps to give an answer of a trouble.

1) strategy is necessary to develop an project idea.

2) to study and know the environment where you are going to work ( ecosystem).

3)   the materials resources to built the ideas.

4) to give a priority order in the context that you study. in this case human needs.