I'm starting Highers tomorrow, and I've chosen to take music. (obviously

)
The thing is, I really want to start Double Bass, but my head of music has no faith in his students and doesn't think I'll be able to learn 5 minutes of Double Bass over the next year.

He wants me to learn a lame piece on glockenspiel for an easy pass. I'm not really that interested in getting straight A's in music, acceptance to my Uni of choice just requires a performance of high quality, not grades.
So, the strings teacher was really backing me up and even offered her spare time to teach me, and there's not a single DB student in the school,(yet two double basses are sitting around gathering dust). Then the ginger prick (music teacher) said that the two wouldn't be accepted as separate instruments. Is this true?

couldn't find the regulations on the sqa website (scottish qualifications authority)
For those too lazy to read, can you sit your A-Levels/Highers/16-year-old American exam on both Electric and Double Bass?