Please choose the correct ending to complete the given sentence: Health: [header] How to prevent head lice [title] Avoid direct head-to-head contact. [step] The common theory as to why children are more susceptible to head lice than adults is that children are less likely to respect personal space. They may also be exposed to situations where head-to-head contact is unavoidable like class nap times or sitting close together side-by-side at their desks.

Ending1: [substeps] Avoiding direct contact is just as important as knowing the proper way to start the lines of communication. Protect your children from disrupting communications if at all possible by strictly avoiding direct eye contact. Ending2: It's as simple as two kids touching heads while leaning over a colouring book. Try to leave space between you and others in order to prevent the spreading of head lice. Ending3: Exposure may cause headache, if applied improperly. [substeps] It can be very difficult to avoid direct head-to-head contact with children at school. Ending4: Natural inclination-deterring prolonged head contact from the testicles is also important to avoiding head lice. [substeps] Do not shave or discard hair from a face, neck, back, or ear.

Answer format: ending1/ending2/ending3/ending4