In this task, you are given a question and answer options for that question. Using this information, you have to classify each text into different topics: medicine, nursery, psychology, chemistry, pharmacology, biology.

Question: Under physiological conditions, the secondary structure of the most frequent DNA in the cells is: 
 Options:  <0> B-DNA. <1> Z-DNA. <2> A-DNA. <3> G-DNA. <4> H-DNA.
biology

Question: They are primary lymphoid organs: 
 Options:  <0> Spleen and lymph nodes <1> The spleen and bone marrow. <2> The thymus and the bone marrow. <3> The pineal gland <4> Peyer's plates and tonsils.
biology

Question: Which of the following cranial nerves has the longest path through a bone canal? 
 Options:  <0> The trigeminal. <1> The pathetic or troclear. <2> The optician <3> The facial. <4> The olfactory.

medicine