$RNAi$ stands for .........

Given below are two statements:
Statement $I$: $Bt$ toxins are insect group specific and coded by a gene $cry$ $IAc$.
Statement $II$: $Bt$ toxin exists as inactive protoxin in $B. \text{ thuringiensis}$. However, after ingestion by the insect, the inactive protoxin gets converted into active form due to alkaline $pH$ of the insect gut.
In the light of the above statements, choose the correct answer from the options given below:

Golden rice is a genetically modified crop. When it is consumed, it is useful in:

The first transgenic plant produced was . . . . . . .

The first transgenic plant was tobacco. It contains a resistance gene against which of the following?

Bacillus thuringiensis forms a protein which is insecticidal. This protein: