Choose the correct option: If you ... nothing, you will stay without this job.

Explanation:

This is a Type 1 conditional sentence. In the 'if' clause, we use the present simple tense. The sentence describes a real or possible situation in the future and its likely result.

The structure is: If + Subject + Present Simple, Subject + Future Simple (will + base verb).

Therefore, the correct verb form to complete the sentence is 'do'.

Answer:

If you do nothing, you will stay without this job.