Read the following passage and answer the questions given below:
No one knows who discovered that the silkworm could be used to clothe people. At first the making of silk was kept a great secret. The kings of china warned their people not to teach strangers the way it was done. They even gave orders that no silk worm eggs were to be allowed out of the country, and that anyone breaking the rules be severely punished.
Silk is a textile that is useful as well as beautiful. It comes from the cocoon of the silkworm. There are four stages in the life of the silkworm. First, there is an egg. The egg batches and a kind of caterpillar known as a silkworm comes out. It eats, grows and bursts out of its skin several times. It then spins a long, slender thread and winds the thread round and round its body. It goes to sleep in this silken nest or cocoon. The silkworm is now a chrysalis. Inside the cocoon, chrysalis changes into butterfly. It then breaks out of the cocoon for the last stage of its life, as an insect. But many millions of silkworms do not live to become butterflies. To get the silk, the silkworkers kill the chrysalises, inside the cocoons by the use of hot steam.