Which of the following items is prohibited in cabin baggage according to Ryanair?

Sharp objects like knives are prohibited in cabin baggage due to safety regulations that aim to ensure the security of all passengers and crew aboard the aircraft. These items pose a potential threat, as they can be used as weapons or could cause injury during unpredictable situations. Airlines, including Ryanair, have strict guidelines regarding what can be carried in the cabin to mitigate these risks.

In contrast, clothing, personal electronics, and books are generally allowed in cabin baggage, as they do not pose the same safety concerns and are deemed secure for transport within the aircraft. The regulations focus on preventing dangerous items from being brought into the passenger cabin, which is why items that could inflict harm, such as knives, are strictly prohibited.