Which insect is reared on the $Opuntia$ (prickly pear) cactus?

Consider the following statements:
$I$. Solid stem in wheat exhibits non-preference by stem sawfly.
$II$. In cotton,smooth leaf and absence of nectar repel bollworms.
$III$. In maize,high aspartic acid,low nitrogen and sugar content protect them from stem borers.
Which of the statements given above are correct?

Which of the following pairs is correctly matched?

Which of the following statements is true regarding pests?

Assertion : In case of vegetatively propagated crops,pure-line selection is not required.
Reason : Hybrid vigour is mostly used in vegetatively propagated plants.

Find the $CORRECT$ match:

Column $A$	Column $B$	Column $C$
$i$. Mackerel	Rastrelliger	Fresh water fish
$ii$. Honey bee	Apis	Wax
$iii$. Mrigal	Taccardia	Marine water fish
$iv$. Silkworm	Bombyx	Mulberry silk