Which of the following increasing order is not correct as mentioned in the property with it?

Options

A. `HCIO lt HClO_(2) lt HClO_(3) lt HClO_(4)` (thermal stability)
B. `HClO_(4) lt HClO_(3) lt HClO_(2) lt HCIO` (oxidising power)
C. `F^(-) lt Cl^(-)lt Br^(-)lt I^(-)` (reducing nature)
D. `HIO_(4) lt ICl lt I_(2) lt HI` (oxidation number of iodine)

Explanation

To solve the question regarding the incorrect increasing order of properties related to the p-block elements, we will analyze each option provided in the question step by step.

### Step-by-Step Solution:

1. **Understanding Thermal Stability**:
- Thermal stability is directly proportional to the oxidation state of the central atom.
- For example, consider the series: HClO, HClO2, HClO3, HClO4.
- Oxidation states: +1 (HClO), +3 (HClO2), +5 (HClO3), +7 (HClO4).
- As the oxidation state increases, the thermal stability also increases. Thus, this order is correct.

2. **Analyzing Oxidizing Power**:
- Oxidizing power is inversely proportional to the oxidation number.
- For the same series: HClO4, HClO3, HClO2, HClO.
- Oxidation states: +7 (HClO4), +5 (HClO3), +3 (HClO2), +1 (HClO).
- As the oxidation state decreases, the oxidizing power increases. Thus, this order is also correct.

3. **Reducing Nature**:
- Reducing power increases down the group in the periodic table.
- For halides: F-, Cl-, Br-, I-.
- I- has the strongest reducing power, followed by Br-, Cl-, and F-.
- This order is correct as well.

4. **Oxidizing Nature of Iodine**:
- Calculate the oxidation states for the following:
- HIO4: +7 (Iodine)
- ICl: +1 (Iodine)
- I2: 0 (Iodine)
- HI: -1 (Iodine)
- The oxidation states are: +7 (HIO4), +1 (ICl), 0 (I2), -1 (HI).
- The order of increasing oxidation state is from +7 to -1, which is incorrect as it suggests a decrease in oxidation state from HIO4 to HI.
- Therefore, this order is incorrect.

### Conclusion:
The incorrect increasing order is related to the oxidizing nature of iodine, specifically the oxidation states from HIO4 to HI. Thus, the answer is option 4.