When drugs cross the placenta during pregnancy, one situation that can occur is that babies may be born with a drug dependency. This can happen if the mother uses certain substances during pregnancy, leading to withdrawal symptoms in the newborn after birth. While not all drug exposure results in dependency, it is a significant risk associated with drug use during pregnancy.
The other options, while they may hold some validity in different contexts (e.g., drug exposure affecting breast milk, potential risks for maternal health), are not directly linked to the immediate consequence of drugs crossing the placenta during pregnancy. It's also important to note that not all drug exposure leads to physical deformities.