Electronic cigarettes (also called electronic nicotine delivery systems or e-cigarettes) come in different sizes and shapes, including “pens,” “mods” (i. e., these types are modified by the user), and “tanks.” Most e-cigarettes contain a battery, a heating device, and a cartridge to hold liquid. The liquid typically contains nicotine, flavorings, and other chemicals. The battery-powered device heats the liquid in the cartridge into an aerosol that the user inhales.

Although the aerosol of e-cigarettes generally has fewer harmful substances than cigarette smoke, e-cigarettes and other products containing nicotine are not safe to use during pregnancy. Nicotine is a health danger for pregnant women and developing babies, and can damage a developing baby’s brain and lungs. Also, some of the flavorings used in e-cigarettes may be harmful to a developing baby.

“Tobacco Use and Pregnancy,”
Centers for Disease Control

Which conclusion does this passage best support?

Traditional cigarettes are less likely to cause complications during pregnancy.
The use of e-cigarettes is a good substitute for traditional cigarettes during pregnancy.
The flavoring in e-cigarettes is less risky for pregnant mothers than nicotine.
Neither e-cigarettes nor traditional cigarettes should be used during pregnancy.