Please choose the correct ending to complete the given sentence: Relationships: [header] How to get a girlfriend if you're ugly [title] Smile at girls. [step] Smiling makes you appear happier to other people, which in turn makes you more attractive. The act of smiling even makes you happier, so it's not just an act, because your brain releases neurotransmitters like dopamine and serotonin when you smile that make you feel good.

Ending1: Smiling is a great way to know that there are people out there who smile naturally. Making eye contact is also a great way to make other people look at you during conversation because it also boosts your confidence. Ending2: [substeps] A smile doesn't have to be related to having beautiful teeth. Cute lips will definitely send a clear message to a girl that you're worth talking to. Ending3: [substeps] Understand that smiling works better with other people because you're actually feeling happier. It's a good habit to break. Ending4: [substeps] In addition, seeing a person smile is actually coded as a reward in other people's brains. When you smile at them, they feel rewarded.

Answer format: ending1/ending2/ending3/ending4