Once upon a time, an old woman had two large water pots. Each hung on the end of a pole(杆子)which she carried across her neck.
One of the pots had a crack in it while the other pot was perfect, From the river to the house, the cracked pot arrived only half full. And the other pot was always full. The perfect pot took pride in its talent.  But the poor cracked pot felt sad for its own disadvantage.
One day by the river the cracked pot said to the woman, "I feel bad about myself, because the crack in me causes water to come out all the way back to your house.”
The old woman smiled and said, "Why are there flowers on your side of the road, but not on the other pot's side? That's because I have always known about your crack. So I planted flowers on your side of the road, and every day while we walk back, you water them. For two years I have been able to pick these beautiful flowers to decorate my house, There would not be this beauty without you. Each of us has our own cracks. But the cracks make our lives so interesting and beautiful."
So, to all the cracked pot friends, have a great day and remember to smell the flowers on your side of the road!
If each of the two pots could be filled with 20 kilos of water, the woman would probably get _______ kilos of water from the river to the house.

A．10

B．20

C．30

D．40

Which of the following is TRUE according to the passage?

A．The woman preferred the perfect pot to the cracked pot.

B．The cracked pot felt more talented than the perfect pot.

C．There were beautiful flowers on both sides of the road.

D．The old woman decorated her house with some flowers.

What can we learn from the story?

A．Everyone has a talent.

B．A true friend is hard to find.

C．Success never comes easily.

D．Mistakes improve our learning,