It remained a question who had to be the pioneer life on a new island. In fact, few people knew it.     Thousands of years ago, in the middle of an ocean, miles from the nearest island, an undersea volcano  broke out. The hot liquid rock piled higher and higher and spread wider and wider. In this way, an island rose up in the sea.     As time went on, hot sun and cool rains made the rock split and break into pieces. Sea waves dashed against the rock. In this way, soil and sand came into being.     It is well known that nothing lived on the naked soil. And then the wind and the birds brought plant seeds, spiders and other creatures there. Only plants could grow first. Only they, in sunlight, could produce food from the minerals of the soil, water and air. While many animals landed on the island, they could find no food. A spider spun its web in vain , because there were no insects for its web to catch. Insects could not stay until there were plants for them to eat. So plants had to be the pioneer life on his new island. According to the passage, the island got its first soil from   _  .
its own rock cool rains the sand brought by the wind sea waves