Read this excerpt from A Doll’s House, by Henrik Ibsen.

Nora. Christine! To think of my not recognising you! And yet how could I--[In a gentle voice.] How you have altered, Christine!

Mrs Linde. Yes, I have indeed. In nine, ten long years--

Nora. Is it so long since we met? I suppose it is. The last eight years have been a happy time for me, I can tell you. And so now you have come into the town, and have taken this long journey in winter--that was plucky of you.

Mrs Linde. I arrived by steamer this morning.

Nora. To have some fun at Christmas-time, of course. How delightful! We will have such fun together! But take off your things. You are not cold, I hope. [Helps her.] Now we will sit down by the stove, and be cosy. No, take this armchair; I will sit here in the rocking-chair. [Takes her hands.] Now you look like your old self again; it was only the first moment--You are a little paler, Christine, and perhaps a little thinner.

Mrs Linde. And much, much older, Nora.

Nora. Perhaps a little older; very, very little; certainly not much. [Stops suddenly and speaks seriously.] What a thoughtless creature I am, chattering away like this. My poor, dear Christine, do forgive me.

What theme is developed through the dialogue?

A. Nora is not able to remember her friend.
B. Mrs. Linde is relieved to sit down and relax with her friend.
C. Time stands still when old friends reminisce.
D. Time and circumstances can change people.