Solution to 4: Bulletin Board

This one contains embedded DNA codons within the text (i.e. trigrams of the letters, A, T, C, or G). The first word of each passage does not count, since they spell out the hint "LOOK AT DNA." Extracting all the relevant capital letters yields GGA GAG CGA ACA CTC ACC GTA CTC GCT CTT TGC GCC CTT CTT AGC GAC TAG CAC CTC. When translated into proteins, they spell out PLACE WHERE TREES LIVE, thus leading to the answer.

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