please help !

Tap the word that “they” refers to.
A) recorders
B) animals
C) scientists

Text below ⬇️

Recently, to address this problem, researchers have been setting up RECORDERS in rainforests to capture the calls of the ANIMALS. Listening to these is like putting a stethoscope to a person’s heart, though SCIENTISTS don’t hear just one animal at a time. When THEY listen, they hear dozens of creatures simultaneously lending their voices to the larger orchestra of rainforest sounds.