Final answer:
Sylvia Plath's father, Otto Plath, who was a professor of biology, died due to complications from diabetes when Sylvia was eight years old.
Step-by-step explanation:
Sylvia Plath was a renowned poet and writer whose father died when she was just eight years old. Otto Plath, who was a professor of biology at Boston University and described as an authoritarian figure, passed away due to complications from diabetes. This loss had a profound impact on Sylvia Plath's life and work, as she struggled with her complex feelings towards him.
It's known that the traumatic effect of her father's death influenced her poetry and writing. Sylvia Plath's father did not die from a car accident, cancer, the Holocaust, or old age, thus the correct answer would be that he passed away due to diabetes, which is not one of the options provided.
Plath's father did not die from cancer, in a car accident, or in the Holocaust. It is important to note that the information provided does not specify the cause of his death.
Therefore, the correct answer is: d) From old age.