Final answer:
The casualty loss if an asset is completely destroyed or stolen is the full market value of the asset.
Step-by-step explanation:
The casualty loss if an asset is completely destroyed or stolen is the full market value of the asset. When an asset is completely destroyed or stolen, the owner experiences a financial loss equivalent to the current market value of the asset. This is because the owner can no longer benefit from the asset or sell it in the future.