"Which one is the best" is obviously a question format, so it makes sense that " which one the best is " should be the correct form. This is very good instinct, and you could even argue that the grammar is good, but at best it's unnatural.
The first example is incorrect. The second and third examples are both correct. Which one you use is mostly a matter of preference, although a hundred appears more frequently than one hundred. There is also another form, an hundred, which was common in the past, but has mostly fallen out of use. See Google Ngram Viewer: a hundred, an hundred, one hundred:
Which is correct: "one or more is" or "one or more are"?
Which came first when saying numbers: "one hundred AND one" or "one ...
When using the word " which " is it necessary to still use " one " after asking a question or do " which " and " which one " have the same meaning? Where do you draw the line on the difference between " which " and " which one " when asking a question that involves more than one answer?
The Wayans Brothers produced some of the most irreverent comedy films of the 1990s and 2000s.
The Wayans brothers are returning to the franchise that helped define early 2000s parody. On Thursday, Paramount Pictures released the first trailer for Scary Movie 6, marking the family’s first ...
Before the reboot and remake era, Marlon Wayans and the Wayans Brothers’ dynasty made parody movies. Wayans has confirmed that “White Chicks 2” and “Don’t Be A Menance 2” are in the works. This summer ...