Hello!
I believe the correct answer is the second option, Enunciation.
Intonation can mean two things: Either how in-tune you are when you sing, or it can refer to how you use your voice pitch to add implied meaning to a word, especially as far as indicating your mood.
Enunciation refers to the clarity of your vowels and consonants, with the latter usually being more important, as the consonant sounds are less resonant. You speak with more precision, using your tongue to form the words.
