Once upon a time, there was a handsome prince. The prince lived with his mother and father in a luxurious castle that overlooked a valley of wildflowers and a distant forest. As the prince grew up, he began to long for a princess. However, the prince wanted to be sure that the princess was a real princess. The queen and king searched far and wide for a real princess, but the prince always found something wrong with the princesses they found. One evening, there was a terrible storm. The wind howled, thunder shook the stone walls, and lightning filled the dark night sky. Through the pelting of the rain, there came a knock at the door. When the king opened the door, he saw a bedraggled girl, soaked to the skin and covered in mud. He ushered her into the castle so that she could warm herself by the fire.

"Why is a young servant girl like you wandering about on such a ferocious night?" queried the king.

The disheveled maiden looked at the king in disbelief. "I am a princess, come to see the prince," she explained, all the while shivering.

The king summoned his wife, the queen, for advice. The queen looked at the hideous creature in disbelief, thinking that no princess would ever allow herself to be found in such a state. She thought quickly and came up with a clever plan. The queen put a small pea at the bottom of a bed and piled twenty mattresses on top of it. When the girl arrived at the room, she had to climb a ladder to reach the top of the bed, where she collapsed in exhaustion.

Bright and early the next morning, the king and queen arrived at the girl's bedchamber. The queen asked the girl how she had slept the night before.

"Absolutely terribly!" bemoaned the maiden. "I have spent the entire night tossing and turning. I don't know whether there is something hard in the bed, or your mattresses are rocks, but my body is black and blue."

The queen and the king stared at the maiden in astonishment. Only a real princess would have such delicate skin that she could feel a pea under twenty mattresses. The queen and king brought her to the prince, who was thrilled to meet a real princess with such an independent spirit.

Look at this picture that illustrates an event from The Princess and the Pea.

A king and queen inspect a bed piled high with mattresses over top of a pea. A young girl sits next to the bed and rubs her back.

Which detail from the picture helps the reader understand that the princess is sore from sleeping on a pea?

The king smiling with his hands folded.
The mattresses stacked on top of each other.
The princess rubbing her back.
The queen inspecting the princess.