The correct option is D Preformed antibodies
In emergency situations where there are serious injuries, tetanus immunization has to be taken into consideration.
In this case the infective agent has already entered the person, therefore preformed antibodies are injected.
The pathogen i.e., Clostridium tetani produces a neurotoxin tetanospasmin and a quick response is required to stop the action of antigen which cannot be done by the formation of our own antibodies as it takes time.
Antibiotics are used to prevent multiplication of Clostridium tetani, thus halting production and release of toxins.
Antitoxins or preformed antibodies have to be given to neutralize unbound toxin.
Weakened germs and dead germs are used in vaccine to develop immunity against them.