元组变量t=（"cat","dog","tiger","human"），t【::–1】的结果是（）

One October morningin 2012, Paul Horton, a 59-year-old retired mechanical engineer and a keenoutdoorsman, climbed onto his mountain bike and took off through hisneighborhood near Lake Travis. Yogi, a six-year-old well-trained dog, camealong. Yogi had done it every morning for nearly three years, happily besidehis master. The two-mile route wound through hilly rural roads to a narrow,forested path. Shortly after turning around to go home, Horton approached anine-inch-tall raised stone edge where the path met the sidewalk. He had jumpedthe edge dozens of times before, but onthis morning somehow he didn’t get enough height, and the bike’s front wheel ran into the edge hard and twistedsharply. Horton, who wasn’t wearing a helmet, flew overthe handlebars, hitting headfirst into the sidewalk. He was knockedunconscious. When he came to, he found himself lying on the ground half a milefrom home.

By Horton’s sidewas Yogi, anxious to continue the trip home. As Horton tried to rise, herealized he could not feel anything below his chest, and blood began to fillhis mouth. Horton whispered ，“Go home. Goget Shearon.” Horton spoke the phrase slowly, again andagain, words he knew the dog wouldunderstand. “Go get” was afamiliar command. Shearon was the name of Horton’swife. For about 45 minutes, Yogi refused to leave his companion’s side. Horton continued commanding Yogi to go. Finally,the dog ranaway.

That morning, Bruceand Maggie Tate, two of Horton’s neighbors, were on a walk in the area whenthey spotted Yogi running down the street, which they found strange.They knew him as a calm and obedient （顺从的）dog. He darted （飞奔）toward them, then away seeming to beg for their attention. When they followed, Yogi dashedoff, leading them somewhere, it seemed.

The wait was aserious pain for Horton. He lost track of time, and it became hard tobreathe. Then Horton heard the faintsound of a dog barking. Yogi ran toward him. The Tates, who were right behindhim, saw Horton’s condition and called for help. Horton was rushed to St. David’sRound Rock Medical Center, where doctors did what they could to mend hisdamaged backbone. Soon after, Horton was sent to St. David’s RehabilitationHospital. His first two visitors？ Shearon and Yogi.

21. What do we know about Paul Horton？

A. He was keen on gardening.

B. He was good at designing bikes.

C. He was fond of outdoor activities.

D. He was devoted to environmental protection.

22. The accident happened when Paul Horton _______.

A. tried to jump over the raised stone edge

B. was on his way to the mountain area

C. took a new narrow forested path

D. climbed onto his mountain bike

23. The word “spotted” in Paragraph3 most probably means “_______”．

A. walked B. saw C. greeted D. chased

24. What can be learned about Yogi from the passage？

A. He liked to do things at will.

B. He seldom went out with his master.

C. He saved his master’s life in the accident.

D. He ran away from his master right after the accident.

25. What can be the best title of the story？

A. Look Before You Leap B. More Haste, Less Speed

C. Love Me, Love My Dog D. A Dog in Need Is a Friend Indeed