Read this following text and answer the questions.

THE GOLDEN STAR FRUIT TREE

    A long time ago there was a rich old man ving in Vietnam. He had two sons with different attitudes The older brother was very greedy and the younger brother was very kind. When the old man died the brothers divided his father's wealth into two parts. The big brother took almost everything. He gave his younger brother only a small piece of land, with a star-fruit tree in front of it. From then on the younger one lived there and made his living only by selling star fruits from the tree. The star fruit tree had an exceptional amount of fruits.

    Unfortunately, a very big raven often came and ate all the ripe fruits. At first he was too afraid of the raven, and did not know what to do. But one day he dared to approach the raven. He begged to it not to eat the fruits. Surprisingly the raven was not angry. He said that he will pay the fruits with gold. From then on, the younger brother and his family could live happily in luxury.

    On the commemoration of his father's death the younger brother invited his older brother to come to his house. At first the big brother refused to come. But because his younger brother insisted, he and his wife finally decided to come. When they got to the younger brother's house they were surprised to see that he was now very rich. He asked his younger brother how he had got all his wealth and the younger brother was happy to tell him the truth. Then the greedy brother and his wife offered the younger brother to trade all their fortune for the star fruit tree.

    The younger brother gladly accepted the offer. When the raven came for the star fruits the older brother made the same plea. As expected the raven told him to bring a 1-meter long bag. Because he was greedy, he asked his wife to make a much longer bag. Because the loud became too heavy for the raven, it swayed, and the greedy brother fell straight down to the sea with his bag and pockets full of gold. He sank very fast down the sea. The older brother finally died. He died because of his greediness.

The golden starfruit tree means ____ (explain)