He was struggling to tie his shoes. I was

问题：

He was struggling to tie his shoes. I was struggling with whether I should help him.
I did, and he was grateful.
"Thank you," he said.
"I’m glad I could help. I just thought it would be easier for me to reach," I said.
He was a disabled man, and forced to look down most of the time. His arms and legs were twisted terribly, and he couldn’t do what the rest of us would consider easy tasks. He always managed to Look up to see how you reacted to his words, however. He had a big smile, making me feel comfort- able.
I was still on my knees by his wheelchair.
"Nice shoes," he said.
"Thanks. No one ever complimented me on them before," I said.
"No one has the same view of the world as I do," he replied.
"Tell me about the world as you see it," I said smiling.
"Most people can see if someone is comfortable with them or not in their eyes. I see it in their feet," he said. "If people keep moving their feet, I just let them go, because I know they’re impatient with me. I don’t want to make people uncomfortable."
"What about me" I asked.
"I could see your compassion. And then you came down to my level. I was the one who was nervous," he said. "I don’t normally have someone look me in the eye. "
"They don’t know what they’re missing," I told him.
"My old face is nothing to brag about. " he said.
"But that smile is so big. "
Yes, and it’s not only a big smile but an attitude.

The disabled man knew people were impatient mostly by their ______.

A．words

B．eyes

C．feet

D．smile