scrolling vs stepping for labelling a large number of things

I'm not sure if this is the correct place to ask this question but I'll try anyway. I have a webapp where the user has to label a large number of separate examples, say 200 of them. Each example is small enough to easily fit in one page. My question is this - is it better to

A) Have a "next" and a "previous" button that allows the user to step through these examples as he/she is progressing through the labelling process OR

B) Have all the examples on a single page and the user will progress through the the labelling process by scrolling down.

I was wondering if there was any known rule for one versus the other in this situation.