We could think that this may be the answer, because we would think that this would be the most basic thing. But truly, if we were to speak as the real business, we would understand that the first true thing that we would first have to learn is to learn on how to swim. And then, we would be able to take into extra activity. But overall, the fear of water is really rare as little kids touch water and drink and play as they would be little. And as you would swim, this fear would go away soon before you know it, and therefore, your answer would then be "Basic swimming capability.".