[題組:第23到25題]
Animals have their special ways to deal with hard times in nature. The superb fairy-wren, one kind of bright-blue bird in Australia, is one example. This year, a ten-year study showed that this small bird has eggs of different sizes in different kinds of weather.
When the weather is hot and dry, there is less food for young superb fairy-wrens, and they die easily. So the mother bird will make larger eggs to help her babies grow stronger inside before they break out of the eggs into the “hungry” world.
However, not all mother birds are able to do this trick. Only those with at least one male child can. When the weather is “good,” the mother will make smaller eggs, and her sons will bring food back for their baby brothers and sisters from the eggs. With her sons’ help, the mother can save more energy to make larger eggs when the weather is bad. Isn’t this amazing?

23.Which is the best title for this reading?
(A) Australia: The Best Place for Birds.
(B) Mother Bird Fights Weather Changes.
(C) Larger Mother Birds Have Larger Eggs.
(D) Family Love: Brothers & Sisters Work Together.