The green revolution succeeded in increasing the yield of crops mainly due to the use of

$I.$ improved varieties of the crops

$II.$ Agro-chemicals

$III.$ Better management practices

Choose the correct option.

Highlight any four areas where genetic modification of plants has been useful.

$A$ : Biofortified crops such as golden rice are helpful in overcoming the problem of night blindness in developing nations.

$R $ : It has enhanced nutritional content of vitamin $A.$

Identify the incorrect statement.

$(i)$ Bacillus thuringiensis are available in sachets as dried spores which are mixed with kerosine and sprayed on to vulnerable plants

$(ii)$ B. thuringiensis are used to control butterfly caterpillars, but leave other insects unharmed

$(iii) $ The toxin of B. thuringiensis is released in the blood of larvae and the larvae get killed

$(iv)$ By the development of methods of genetic engineering B. thuringiensis toxin genes have been introduced

Tobacco plants resistant to a nematode have been developed by the introduction of $DNA$ that produces (in the host cells)