被俄罗斯人称为“母亲河”的是（　　）

根据短文内容，从短文后的选项中选出能填入空白处的最佳选项，并在答题卡上将该项涂黑。每个选项限选一次。

Teacher: What do you want to do in your future?

Lily: I like shopping and talking to people. ____ Maybe selling clothes is a good business for me.

Ryan: My hobbies are playing computer games and making friends online. ____ I guess I will learn more about computers and make super-smart computer programs.

Bill: My parents have kept lots of pets since I was little. ____ Those stories have always stayed in my mind. One day, I will share them with people by drawing and writing books.

Anna: Though my mom and two sisters are all doctors, I'm sure I will stay as far away from a hospital as I can. ____ I'll keep strong by playing my favorite sport, tennis, every day. One day I'll join the national team.

我们的鼻腔吸进的空气和口腔吃进的食物，进入人体后都要经过的器官是（　　）

数轴上到原点的距离等于4的数是____ ．

若函数f（x）=a^﹣x（a＞0，a≠1）是定义域为R的增函数，则函数f（x）=log_a（x+1）的图象大致是（　　）