Explanation:

- Option 1: Maximum

- Total utility reaches its maximum when marginal utility becomes zero because additional consumption no longer adds to overall satisfaction.

- Option 2: Diminishing

- Total utility may increase at a decreasing rate when marginal utility diminishes but remains positive.

- Option 3: Increasing

- Total utility continues to increase as long as marginal utility is positive, as each unit of consumption adds to total satisfaction.

- Option 4: Minimum

- This is incorrect because having a positive marginal utility means total utility has not reached its minimum.