What does $Bt$ stand for in the popular crop $Bt-cotton$?

What is the full form of $GMO$?

The bacterium $Bacillus$ $thuringiensis$ is widely used in contemporary biology as

Given below are $2$ statements: one is labelled as Assertion $(A)$ and other is labelled as Reason $(R)$.
Assertion $(A) :-$ Toxic insecticidal protein of Bacillus thuringiensis does not kill Bacillus itself.
Reason $(R) :-$ In Bacillus,$Bt$ toxin protein exists as inactive protoxins.
Correct answer from the options given below :

The $Bt$ (Bacillus thuringiensis) strain was developed as a ...........

Plants are genetically engineered with novel genes by