Post-immunization serological test results for a health care worker who has completed the series of vaccinations against hepatitis B is informed that their anti-HBsAg is less than the value required for immunity. The health care worker should

undergo the full series of hepatitis B vaccinations followed by post-immunization testing.

receive one additional vaccination followed by post-immunization testing.

refrain from performing any exposure-prone procedures for a period of 3-6 months followed by a full series of hepatitis B vaccinations.

have liver function tests performed to assess liver damage from a previous hepatitis B infection.