I think you are right - it was meant to be answer choice C based on what she was talking about....halogenation is a tricky reaction (in reality) as multiple products are going to be favored. In reality, the secondary or even primary halogenated product might actually be favored, as you start to play a bit of an odds game (i.e., tertiary position may be thermodynamically favored, but if 9 primary positions exist elsewhere on the molecule, bromine may be more likely to take up one of those positions instead).
Again, when you are doing your studying, try not to get too caught up in all the specific details....learn the basics and do literally 1000's of practice problems....it's the only way to become strong on the MCAT!
Good luck!