Please answer a question about the following article about Eton College:

The opposite of a Show Up is a "Rip". This is for sub-standard work, which is sometimes torn at the top of the page/sheet and must be submitted to the boy's housemaster for signature. Boys who accumulate rips are liable to be given a "White Ticket", which must be signed by all his teachers and may be accompanied by other punishments, usually involving doing domestic chores or writing lines. In recent times,[when?] a milder form of the rip, 'sign for information', colloquially known as an "info", has been introduced, which must also be signed by the boy's housemaster and tutor.

Who must sign a White Ticket?
all his teachers