Hey,

Good question - I would say pretty much 99% of the time (probably closer to 100% of the time for MCAT Chem) the trans diastereomer is more stable because of sterics.

It is true that H bonding can change things, but this stabilization tends to be only really significant in 5 member rings or 6 member rings (with a few exception for fused ring systems).

If this is going to switch cis/trans stability, they would heavily imply it in the question as it's a bit more of an advanced topic (recall that they stated stabilities for the 7 member ring H bond case and had you rationalize based on information given).

For your base knowledge, unless you're asked to do something otherwise, keep it simple and assume that CIS is higher energy than TRANS due to sterics.