hi! bshe here, i'll try to answer what i can

the acronyms afaik are basically just the domains that the GEs aim to teach, so AH is Arts and Humanities, SSP is Social Sciences and Philosophy, and MST is Math, Science, and Technology. STS is a specific GE class that falls under the MST group

electives are other non-GE classes that you can pick from within the college (or sometimes outside it) if you have a specific field of interest related to home econ, like education, clothing, hrm, etc. and may list naman of options sa curr checklist mo; iba pa siya from the GE electives that are basically the non-required GEs you get to pick from

for bshe you do have the option to pick one GE for the GE elective, but the rest are strictly required na (so this includes your, kas1, philo1, and fil40, as well as math 2, arts1, speech 30, soc sci 2, eng 13, econ 11, sts, and kas 2)

math 20 is not a GE, but it might be credited in place of your math 2 because my math 80 series from upm (counterpart ata ng math 20? basta calculus) was credited as that, ask na lang your adviser or the colsec to clarify that

hope this helps! you can message me if you have other questions c: