Tina negligently hits student Susie with her car. Which of the following is true?

a. Tina has no duty to come to the aid of Susie.

b. Tina has a duty to come to the aid of Susie because she negligently hit her.

c. Tina has a duty to come to the aid of Susie only if police are not on the scene within a reasonable amount of time.

d. Tina has a duty to come to the aid of Susie only if Susie has insurance.

e. Tina has a duty to come to the aid of Susie only if no one else is willing to do so.