Select the mismatched pair from the following:

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

When two unrelated individuals or lines are crossed,the performance of $F_1$ hybrid is often superior to both its parents. This phenomenon is called

Choose the correct pair.

Consider the following four measures $(I-IV)$ that could be taken to successfully grow chickpea in an area where bacterial blight is common.
$I.$ Spray with Bordeaux mixture.
$II.$ Control of the insect vector of the disease pathogen.
$III.$ Use of disease-free seeds only.
$IV.$ Use of varieties resistant to the disease.
Which of the above measures can control the disease?

Which of the following is an incorrect pair regarding the major dairies of Gujarat?