Doug and Manuel received the following interest income in the current year:

Savings account opened at Greenbacks Bank $$4,000$

U$.$S$.$Treasury bonds $250$

Interest on State of Iowa bonds $200$

Interest on Federal tax refund $150$

Interest on state income tax refund $75$

Greenbacks Bank also gave Doug and Manuel a cellular phone $($worth $$100)$ for opening the savings account. What amount of interest income should they report on their joint income tax return?

a$.$ $$4,300.$

b$.$ $$4,775.$

c$.$ $$4,575.$

d$.$ $$4,675.$