How can lead enter the body?

Lead can enter the body through several routes, and the option that states it can be inhaled as dust, swallowed, or ingested via paint chips accurately reflects the most common ways of lead exposure.

When lead-based paint deteriorates, it can create dust particles that can be easily inhaled, especially in older homes where such paint was used. Children, in particular, are at high risk as they may put objects or their hands, which may have lead dust on them, into their mouths. Additionally, lead can enter the body if someone eats paint chips that contain lead, which can also be a concern in homes and environments where lead paint has been used.

In contrast, the other options suggest overly limited or incorrect pathways for lead to enter the body. Direct exposure to paint is not the sole method, as lead dust is often more insidious. Drinking contaminated water is certainly a valid exposure pathway, but it does not encompass the broader risks associated with dust and paint ingestion. Moreover, lead does not enter the body merely through injection as this method is not applicable in context with general exposure scenarios related to lead. Therefore, the option that includes multiple routes of entry provides a comprehensive understanding of lead exposure risks.