If You Were Giving to the Poor and Are Guided

If you were giving to the poor and are guided by Islamic principles, what guidelines would you have to follow?

A) Ensuring that someone has witnessed you being charitable to verify the act.
B) Setting aside and donating a certain percentage of your earnings, depending on your income.
C) Doing it in secrecy to maintain your humility and spare the recipient from embarrassment.
D) Providing options for the type of donation the recipient can accept, such as money or goods.