Final answer:
Under 12 CFR 9, a bank administering a common trust fund that has a defaulted fixed income asset in its portfolio must immediately write-off the asset against fund earnings.
Step-by-step explanation:
Under 12 CFR 9, a bank administering a common trust fund that has a defaulted fixed income asset in its portfolio must immediately write-off the asset against fund earnings.
So, the correct option is: 1) Must immediately write-off the asset against fund earnings.