Which of the following is an example of a teratogen?

• A. Syphilis
• B. Vitamin C
• C. Folate
• D. Caffeine

Answer: (A)

Teratogens are agents that can cause birth defects or fetal harm if a mother is exposed during pregnancy. Syphilis fits this description because it’s an infectious disease that can be transmitted from mother to fetus across the placenta, leading to congenital syphilis with a range of severe fetal problems and even pregnancy loss if untreated.

The other options are not teratogens in the typical sense. Vitamin C and folate are essential nutrients that support healthy development; in fact, folate helps prevent neural tube defects. Caffeine, at normal dietary levels, is not considered a classic teratogen.