Passengers are allowed to bring a limited amount of liquids, aerosols, and gels in their carry-on baggage when traveling through London Stansted Airport, as long as they comply with the 100ml/3.4oz rule and are placed in a clear, plastic, sealable bag. Exceptions are made for necessary medication, baby food, and special dietary requirements. It is always recommended to check the specific guidelines and regulations of your airline before traveling.