Which method is used to make tobacco plants resistant to pests?

Crystals of $Bt$ toxin produced by some bacteria do not kill the bacteria themselves because

Consider the following statements:
$I$. Flavr Savr is a genetically modified tomato,which remains fresh and retains its flavour much longer than the normal tomato due to the blocking of the synthesis of the fruit-softening enzyme polygalacturonase.
$II$. Recently,the $US$ government has patented the Indian 'basmati' rice as Rice-tec.
$III$. Viruses,bacteria,and some other harmful organisms can be used as bioweapons in biological warfare.
Which of the statements given above are correct?

In $RNA$ interference,the $dsRNA$ molecule prevents . . . . . . .

Golden rice is enriched with which of the following?

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: