Final answer:
A spontaneous abortion requires a D&C, which is a surgical procedure to remove tissue from the uterus.
Step-by-step explanation:
The type of abortion that requires a D&C is a spontaneous abortion.
A D&C, short for dilation and curettage, is a surgical procedure that removes tissue from the uterus. In the case of a spontaneous abortion, also known as a miscarriage, a D&C may be performed if the pregnancy loss is incomplete and there is still tissue remaining in the uterus that needs to be removed. This is different from a complete, spontaneous, or threatened abortion (miscarriage), where the tissue is expelled naturally or the pregnancy continues despite complications.
Spontaneous abortion can occur due to various reasons such as genetic abnormalities, hormonal imbalances, or medical conditions that affect the development of the fetus.