Explanation:

Correct option 4: which

The human brain regulates and coordinates all the voluntary and involuntary moves ______ we make.

Let’s analyze the options:

1. what –  Incorrect“What” is typically used to ask a question or as a pronoun meaning “the thing that.” It doesn't fit this relative clause structure.

2. whatever – Incorrect
   "Whatever" means "anything that" or "no matter what," which implies a broader or more general meaning. It doesn't fit because we're talking about specific known actions.

3. whichever – Incorrect
   "Whichever" is used when choosing between options, often meaning "any one that" — again, this is not suitable here since there's no choice implied.

4. which –  Correct
   "Which" is a relative pronoun that refers back to a noun ("moves") and introduces a defining clause. It's the most grammatically and contextually appropriate.