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: Ribosomes have three binding sites for the transfer RNAs (RNAs), which are:
Options: <0> Site A of acetyl, P of propyl and E of ethyl. <1> A site of aminoacyl, P of peptidyl and E of exit (from English, exit). <2> A site of aminoacyl, peptidyl P and transferase T of the peptide. <3> Site A of previous, P of posterior and E of entry (of English, entry). <4> A site of aminoacyl, peptidyl P and terminating T.
pharmacology

Question: In a three-point test crossover study, a negative interference indicates that:
Options: <0> More double crossings have occurred than expected. <1> There have been fewer double crossings than expected. <2> The match coefficient is less than 1. <3> A simple crossover decreases the likelihood of a double crossover occurring. <4> There have been fewer simple cross-links than expected.
biology

Question: The trophoblast develops from:
Options: <0> The outer layer of the blastocyst. <1> The internal cell mass. <2> The zona pellucida. <3> The bilaminar germinative disc. <4> The endometrium
biology