Final answer:
The erroneous student statement that "Condoms are only for preventing pregnancy" indicates a misunderstanding, as condoms also play a critical role in reducing the risk of sexually transmitted infections, although not providing complete protection.
Step-by-step explanation:
The statement by the students that indicates a need for additional teaching about condom use is: "Condoms are only for preventing pregnancy." This statement is inaccurate as condoms are not only used to prevent pregnancy but also provide a significant but not absolute barrier against sexually transmitted infections (STIs).
While the use of condoms can greatly reduce the risk of transmission of many STIs, they need to be used consistently and correctly to be effective. Condoms are most effective when made out of latex, as some pathogens can pass through the pores in natural skin condoms. It's also important to educate that condoms cannot prevent STIs in areas of the body that aren't covered and that behaviors like washing after intercourse do not prevent STI transmission.