Explanation:

- Purely financial transactions: These include the buying and selling of stocks and bonds, which do not represent actual production activity. Transactions purely financial in nature don't get included in GNP as they don't translate to real goods or services produced.

- Transfer of used goods and non-market goods and services: Used goods' sales aren’t included in GNP since they were accounted for in the GNP of prior years when they were first sold as new goods. Non-market goods and services, like household chores, aren’t included because they don’t involve market transactions.

- Illegal activities and the value of leisure: The value of illegal activities is not recorded in GNP due to the challenge in measurement and legality issues. Similarly, leisure, though valuable, does not directly result in market transactions.

- All of these: All the given options are indeed excluded from GNP measurement.