None of them. All of them are equally good. It depends on how you are going to use it. It's about the execution and the content. Take the social network that you think could be adapted to your needs and start being a professional. All social networks allow you to grow and increase your audience and, if you can grow and increase your audience, you can generate traffic. Then, try to find the platform that suits your needs.
If you want instant traffic, try Reddit, but keep in mind that self-promotion is hated, that they will reject it and, sometimes, even criticize it. It's up to you.