There are two possible ways to A/B test some landers in its usual meaning.

1. You create a Flow with a Path, which contains two or more Landers with the same Offers in each lander. The flow will rotate these landers according to Weights and Rules (obviously you should spread weights evenly for every lander and should not add additional landers to rules). This flow should be selected in you Campaign. 

Then you manually choose the winner depending on stats.

2. Or you create a Campaign without a Flow but only with a Path following same recommendations.