$A$ infects the roots of tobacco plants,which reduces the production of tobacco.

The toxin produced by the gene of $Bacillus \text{ } thuringiensis$ is effective against which of the following?

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?

Cultivation of $Bt$ cotton has been much in the news. The prefix $Bt$ means

$Bt$ cotton is used to destroy:

Select the appropriate option for $RNAi$.