Final answer:
The content of the forename field is 'jo'hn' (option 1), as that is the input provided for the user's given name, while 'smith' is the surname or last name.
Step-by-step explanation:
The content of the forename field, when a user supplies the input 'jo'hn' for the forename and 'smith' for the surname, would be option 1) jo'hn. This is because the forename refers to the given or first name of the user, which in this case is 'jo'hn'. The surname, on the other hand, represents the family name or last name, which in this instance is 'smith'. When gathering user input for forename and surname in a form, it is important to accurately capture and store the information as entered by the user, ensuring that special characters such as the single quote in 'jo'hn' are properly handled to prevent issues such as SQL Injection if this data will be interacted with a database.