A 23-year-old medical student who had four injections of DTaP in her first year of life and a booster at age 12 years, but not subsequent tetanus immunization, is bitten by a mouse while performing an experiment. She should be given

tetanus toxoid.

Explanation:

Okay, things to note from the question above are: the medical student had four injections in or before she clocked 12 years of age.

The four injections given to the student when she was small should be FIVE instead of the four given for tetanus immunization and she should have been given a booster twice. Now, at 23 years old, is bitten by a mouse while performing an experiment. Sine she was not immunized against tetanus while she was young she should be given a tetanus toxoid.

Also, her wound should be closed since tetanus enters the body through a cut it say an open wound. The tetanus toxoid helps in the immunity against tetanus.