Are Written Constitutions the Best Guarantor of Equal Rights

Are written constitutions the best guarantor of equal rights?

A) Yes, all countries write equal rights into their constitutions.
B) Yes, all countries abide by their written constitutions.
C) Yes, most countries mimic the United States' rights-based legal structures.
D) No, some countries do not abide by rights protections written into their constitutions.
E) No, most countries derive rights protections from international treaties instead of national constitutions.