Help needed: UCAS - entering GCSE subject names

Hey guys! So, this probably seem so like the dumbest thread ever created, but I'm trying to put in my GCSE grades for my application and I'm confused by discrepancies between the UCAS options list and the specifics on my form.

For example: UCAS lists 'Mathematics A (Linear)' and my form says 'Mathematics A (Linear) Option H'
So do I go with the UCAS option, or do I type in the very specific thing from my form?
There are multiple instances like this.

Also, it says to 'insert the exam code if you have it'...I have all of them, and this would simplify the matter, were I not completely confused as to the fact that there is nowhere to put them?? It has subject name, the date, the board, and the grade...and nothing else?

Please help me! I'm probably just a dumbass but I'm so confused.

DO you have your certificates? That's what you should be entering - the "Option H" and the like on your results slips and school/college records are extra details that wont appear on your certificates.