Answer:
bacteria
Step-by-step explanation:
'Bt' crops are genetically modified crops that contains a certain gene of a bacteria called Bacillus thuringiensis. The name of this GM or transgenic crop was coined from the bacteria used.
The gene coding for the toxic traits of the bacteria are added into Bt crops e.g cotton, hence, the crops become resistant to pest attack. Therefore, according to this question, BT crops are developed by adding traits from BACTERIA.