ok so
log₁₂₅25
remember
logₐy=x means aˣ=y
and
remember that (xⁿ)ᵇ=xⁿᵇ
and
if aⁿ=aᵇ where a=a, then n=b
so
log₁₂₅25=x means
125ˣ=25
to solve, convert to same base
125=5³
25=5²
(5³)ˣ=5² means
5³ˣ=5²
therefor
3x=2
solve
divide both sides by 3
x=2/3
answer is C