Consumption of which one of the following foods can prevent the kind of blindness associated with vitamin $A$ deficiency?

Golden rice is a genetically modified crop plant. Which of the following is synthesized by the gene inserted into it?

$Bt$ cotton variety that was developed by the introduction of toxin gene of $Bacillus$ $thuringiensis$ $(Bt)$ is resistant to

$RNA$ interference involves

Consider the following statements about $Bt$:
$I.$ The bacteria $Bacillus$ $thuringiensis$ $(Bt)$ are used to control butterfly caterpillars.
$II.$ Fresh spores of $Bt$ are mixed with water and sprayed on crops such as brassicas and fruit trees.
$III.$ Insect larvae,after eating these,are killed by the toxin released in their gut.
$IV.$ $Bt$ toxin genes have been introduced into plants to provide resistance to pests.
Which of the statements given above are correct?

Cotton is protected from bollworm by using the bacterium . . . . . . .