Explanation:

- A Promissory Note is a financial instrument in which one party (the maker) promises in writing to pay a definite sum of money to another party (the payee), either at a fixed future date or on demand.

- There are only 2 parties involved in a promissory note:

- Maker: The one who makes the promise to pay.

- Payee: The one to whom the payment is promised.

- Other options like 3, 4, 5, or 6 parties are incorrect in the context of a promissory note. These options may sometimes apply to other instruments like bills of exchange but not here.

- Therefore, the correct option is:

Option:3 - 2 Parties