1
If I have to choose between liberal and conservative, I prefer the former one.
If I have to choose between liberal and conservative, I prefer the former.
Use the former, without one, to refer to the first of two people or things that have been mentioned.
2
Of the three options, I prefer the former.
Of the three options, I prefer the first.
Use the former only when two people or things have been mentioned. When there are more than two, use the first.
See LATTER