Q: In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.
Question: Diphyllobothrium latum competes with its definitive host for the vitamin:
Options: <1> TO. <2> B 12 <3> C. <4> D. <5> AND.
A:
2