I still remember the last time I went to the playground with two of my children. It had rained during the night and the playground was very muddy  . They had just put on clean clothes, so I was a little worried about the mud on the playground. It was not long before Kathy got her beautiful skirt dirty on the playground. She dug through the rocks. I was about to blame   her for getting her clothes dirty when she ran towards me with a smile on her face. When she got to me, she handed me a little heart-shaped rock and said, "Here, Mom! Here is a heart for you --just because I love you! Keep it!" With tears in my eyes, I thanked her. Should I blame her for getting her clothes muddy? No way! I still have that little heart-shaped rock. It is one of the best gifts that I have ever received. I realized that many times it was not necessary for us adults to worry about the small things our children did. Let them do what they'd like to. I will spend a lot more time on the playground with my children. I'm sure I will learn a lot from them. It makes me think of the days when my grandfather told me, "You would not enter the kingdom of happiness until you pretended   to be a small child." The author was deeply moved by her daughter's   _  .
digging task on the playground special way to show her love smile on her face when running love of the muddy playground
Question: I still remember the last time I went to the playground with two of my children. It had rained during the night and the playground was very muddy  . They had just put on clean clothes, so I was a little worried about the mud on the playground. It was not long before Kathy got her beautiful skirt dirty on the playground. She dug through the rocks. I was about to blame   her for getting her clothes dirty when she ran towards me with a smile on her face. When she got to me, she handed me a little heart-shaped rock and said, "Here, Mom! Here is a heart for you --just because I love you! Keep it!" With tears in my eyes, I thanked her. Should I blame her for getting her clothes muddy? No way! I still have that little heart-shaped rock. It is one of the best gifts that I have ever received. I realized that many times it was not necessary for us adults to worry about the small things our children did. Let them do what they'd like to. I will spend a lot more time on the playground with my children. I'm sure I will learn a lot from them. It makes me think of the days when my grandfather told me, "You would not enter the kingdom of happiness until you pretended   to be a small child." The author was deeply moved by her daughter's   _  .
A. digging task on the playground
B. special way to show her love
C. smile on her face when running
D. love of the muddy playground
Answer: