Which of the following situations do not count as days of personal use by the owner of rental property?

a. The taxpayer stays at the house for 10 days while making repairs to the property.

b. The taxpayer's sister pays a fair rental price to rent the property for 10 days during the year.

c. The taxpayer donates a week of use to a qualified charitable organization.

d. All of the above count as days of personal use.

e. None of the above count as days of personal use.