MBC software will report all ways that A is combined with other items: 1-way, 2-ways, 3-ways, etc.
The manual talks about comparing actual joint likelihoods observed to expected joint likelihoods. For example, if A and B separately have indendent likelihoods of 0.1 and 0.1, then the expected joint likelihood would be 0.1 x 0.1 = 0.01. But, you can compare the expected likelihood to the actual joint likelihood as tabulated by the software.
The MBC software does not report expected joint probabilities, but only actual ones. Expected joint probabilities you'd need to compute on your own.