Explanation:

The odd one out in this list is option 'B' - Matching Cost.

Full Disclosure:
- Full Disclosure is a principle in accounting that requires all relevant information to be provided in the financial statements and accompanying notes.
- This principle ensures that users of the financial statements have all the necessary information to make informed decisions about the entity.
- It aims to provide transparency and prevent any hidden or undisclosed information that may mislead users.

Materiality:
- Materiality is a concept in accounting that relates to the significance or relevance of information in the financial statements.
- It requires the disclosure of information that could influence the economic decisions of users.
- Materiality is determined based on the nature and magnitude of an item, and its omission or misstatement could potentially impact the financial statements' users' decisions.

Prudence:
- Prudence is an accounting principle that suggests caution in preparing financial statements.
- It encourages the exercise of caution when making judgments about uncertain events or transactions.
- Prudence requires the recognition of losses and liabilities as soon as they are probable, but it does not allow overstatement of assets or income until they are realized.

Matching Cost:
- Matching Cost is a concept in accounting that relates to the matching of expenses with the revenues they helped generate.
- It ensures that expenses are recognized in the same accounting period as the revenue they helped to generate.
- This principle helps in providing a more accurate representation of the entity's financial performance.

Conclusion:
- In this list, all the options are accounting principles or concepts except for 'Matching Cost,' which is a specific accounting method or concept related to expense recognition.
- Therefore, the odd one out is option 'B' - Matching Cost.