If $A>B$, $B>C$ and $C>D$, then which of the following conclusions is definitely wrong?

We are given the following relations:
1. $A>B$
2. $B>C$
3. $C>D$

Combining these inequalities into a single linear chain sequence, we get:

$$A>B>C>D$$

From this combined chain inequality, we can check each conclusion:

* Option A: $A>D$ is true since $A$ is greater than all subsequent elements.
* Option B: $A>C$ is true since $A>B>C$.
* Option C: $D>A$ is completely false (definitely wrong) because $A>D$.
* Option D: $B>D$ is true since $B>C>D$.

Therefore, conclusion C is definitely wrong.