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Some butterflies lay their eggs on just one kind of plant. By tasting the plant, they know which one is right. Sometimes butterflies taste the wrong plant. So they fly to another plant and taste again. When they find the right plant, they lay their eggs there. Soon the eggs hatch. The hungry babies eat the plant their mother chose!
This story mainly tells
A. When baby butterflies come out of eggs.
B. How butterflies choose where to lay eggs.
C. What flies from one plant to another.
D. How butterflies always taste the right plant.
B. How butterflies choose where to lay eggs.