Of the business activities listed here, which activities can be conducted through U.S.-regulated holding companies today?

a. Data processing companies

b. Office furniture sales

c. Auto and truck leasing companies

d. General life insurance and property-casualty insurance sales

e. Savings and loan associations

f. Mortgage companies

g. General insurance underwriting activities

h. Professional advertising services

i. Underwriting of new common stock issues by nonfinancial corporations

j. Real estate development companies

k. Merchant banks

l. Hedge funds