Step 1: Know the two big ideas:
In active immunity the body makes its own antibodies after meeting an antigen.
In passive immunity ready-made antibodies are given to the person from outside.
Step 2: Apply to antivenom:
Antivenom contains antibodies (antitoxins) raised in another animal, such as a horse, against snake venom.
These antibodies are injected into the patient, so the patient does not make them. This is passive immunity.
Since it is given by an injection and not obtained by natural routes, it is artificial.
Step 3: Why the others are wrong:
(A) and (B) are active types. They need the body to produce antibodies, which does not happen here.
(C) natural passive immunity is the transfer of antibodies from mother to child through the placenta or colostrum.
Final Answer:
Antivenom is artificial passive immunity.
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