British Education System – Inspiration D

My daughter, a bright individual, however suffers with dyslexia is in the bottom sets. She is currently in year 10 doing some of her GCSE exams.
She comes home saying I hope I get a D, ‘why a D not an A’ I ask, because I am in the bottom sets the top mark I can achieve is a C, and I don’t think I did that well today. WHAT is that all about?
So basically this government is telling our children they can achieve a C if they really put their minds, blood sweat and tears into their schooling………………… Whoop whoop.
Have you ever heard such rubbish?
Now she got a C in her mock and was chuffed as punch! so why did the school not let her set the other exam papers so she could achieve an A or B?
Is it just me?