Karen laughed at her mom because _____________ .A．

单项选择题

Passage 1 The elevator door slid open. The crowd inside let out a collective gasp of excitement. But no one was more excited than my mom. This 110-pound woman is not normally rude, but suddenly she rushed through the door, nearly knocking over an elderly German tourist. My mom wasn’t interested in the sights; she just wanted air. If there’s one thing that frightens my mom more than packed spaces, it’s heights. We were now 889 feet above the Paris cityscape. Maybe we should have taken the Eiffel Tower off our “to do”list. By the time I caught up with her, she had pressed her entire body against a huge steel girder（大梁）. I couldn’t help but laugh. “What” she said defensively, her arms wrapped around the support and her face flushed. “I’m having a great time. ” “Yeah, I can tell. Let’s go, ”I said. My mom replied,“I can’t. ” Amidst the twinkling reflection of the City of Lights, I saw terror in her eyes. She was so scared of heights, she couldn’t move. I was going to have to think of something—and fast. “I know, Mom!”I shouted, making her jump. “We don’t have to get back in the elevator. We can walk all the way down. ” Before she could think about it, I took her arm and led her over to the stairs. Finally, after 20 minutes, we headed down the last flight. “See That wasn’t so bad. ” I pushed on the steel exit gate. The gate didn’t move. I felt a fit of panic. I pushed again, still no movement. I shoved again and again against the gate. Out of breath, I felt on the verge of tears. “Qu’est-ce que c’est la probleme” A young French security guard stood on the other side of the gate. He repeated his question. The fact that I didn’t understand French only made me panic more. I banged violently on the door, and rocked against it—still nothing. The guard smiled now. He pointed up and said in English, “The sign. Read it. ”I followed his pointing finger to a sign that hung above the gate. It said:“Tirez.” I looked at the guard blankly. What did that mean “The sign,” the guard told me. “It says, Pull. ” Stepping back, I stopped pushing the gate. I pulled instead. It swung open easily. Now my face burned with embarrassment, not panic. “Karen, you really need to learn to relax,” my mom said, laughing as she breezed past me.

Karen laughed at her mom because _____________ .

A．she was too nervous
B．she was too excited
C．she was having a great time
D．she was standing against a huge girder