When one wishes to analyse a subject you must do what at great length? Choose the most suitable option to answer the above question. Options：  A. look at  B. use calculator  C. come to conclusion  D. learn new  E. think about
E

It turned out it wasn't a kidney stone, what might it have been a stone in? Choose the most suitable option to answer the above question. Options：  A. gallbladder  B. creek bed  C. driveway  D. river bed  E. gravel
A

What do you need to write a letter? Choose the most suitable option to answer the above question. Options：  A. have paper  B. literate  C. not give up  D. move fingers  E. to keep warm
A

Playing piano and other creative activities need what? Choose the most suitable option to answer the above question. Options：  A. make music  B. inspiration  C. musical sounds  D. making music  E. dancing
B