The second.
second
The accented syllable in the word unfold is the second syllable ([un-FOLD] - /ʌnˈfoʊld/ in IPA).
First. It's UN-fold, as opposed to un-FOLD
first syllable
The word balance is a unstressed first syllable.
It is a two syllable word. The first syllable is Bett- and the second is -er.
'Accept' is neither a 'first' nor a 'second' syllable word. It is a two syllable word.
"Dolphin" is a first-syllable word. The primary stress is on the first syllable in English pronunciation.
The first.
The accented syllable in the word "alert" is the first syllable.
first
Deliver is stressed on the second syllable.