Toxins that primarily affect a pregnancy in the embryonic stage (up to 8 weeks of gestation) are known as which of the following?

A) Teratogens
B) Fetotoxins
C) Carcinogens
D) Neurotoxicants

Teratogens

Agents or factors that cause malformation of an embryo or fetus, including certain drugs, infections, and chemicals.

Embryonic Stage

The period during pregnancy from the second to the eighth week post-conception, when significant growth and development of the embryo occur.

Gestation

The period of time a fetus develops inside the mother's womb or uterus, typically lasting about 40 weeks in humans from the last menstrual period.