Complete the dialogue with proper words or sentences.

A: Good morning, madam!

B: Good morning, sir!

A: You look worried. 1._____________?

B: My son got lost when I was talking with my friend in the park. I've looked

    for him everywhere, but I can't find him. What shall I do?

A: 2._____________. Tell us something about him, and we can help you.

B: Thank you, sir.

A: Now please tell me 3._____________.

B: He's six years old.

A: 4._____________?

B: He's thin and tall with big eyes.

A: What is he wearing today?

B: He's wearing a white T-shirt and blue jeans.

A: 5._____________?

B: It's 13803677057.

A: OK. We'll call you as soon as we find him.

B: Thank you very much.

连续式水平支撑适于（）的沟槽开挖中的支护。

A.地下水很少，深度在2m以内

B.地下水很少，深度在3m以内

C.地下水很少，深度在3～5m

D.地下水很多、深度在4m以内