Methylation of Guanine to Produce O⁶-Methylguanine (MG)results in What Change $\rarr$

Methylation of guanine to produce O⁶-methylguanine (mG) results in what change to DNA?

A) mG frequently pairs with thymine resulting in a GC $\rarr$ AT mutation
B) mG loses its methoxy group resulting in hydrogen bonding with adenine and a bulge in the double helix
C) mG is prone to deamination and eventually, depurination
D) repair of mG adducts uses a radical mechanism that has the potential to further damage adjacent bases, particularly thymine
E) none of the above