Can you go into more detail on what this question entails? I am a little confused!
Explanation:
simple and honest . very fast and saves time
I would say A but D could also be said softly
The last answer sets the most formal tone; "Hello! I was very pleased to meet you at the party last week." the rest are very casual.
Discomfiture
noun. [mass noun] A feeling of unease or embarrassment; awkwardness. 'many MPs are secretly enjoying his discomfiture
