SMELL is to NOSE, as SOUND is to: A ear
B: eye
C: music
D: trumpet
E: None of these

Ear

Explanation:

We use our nose to smell and our ears to hear.

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.