The correct order of the dynamic markings from softest to loudest is:
B. p, mp, mf, f
These are its letter meanings.
p - piano → This means "soft"
mp - mezzo-piano → This means "half soft"
mf - mezzo-forte → This means "half loud"
f - forte → This means "loud"
The overall ranking of dynamic markings are:
ppp - pianississimo. This means "very very soft"
pp - pianissimo. This
means "very soft".
più p - più piano. This means "softer".
p
mp
mf
f
più f - più forte. This means "louder".
ff - fortissimo. This means "very loud"
fff - fortississimo. This means
"very very loud"