Which is a similar term to $Hybrid$ $vigour$?

Which of the following statements is consistent with obtaining a progeny with genetic variation?

Consider the following four statements $(a-d)$ regarding the successful cultivation of chickpea in an area where bacterial blight is common:
$(a)$ Spraying of Bordeaux mixture.
$(b)$ Control of the disease vector.
$(c)$ Use of disease-free seeds.
$(d)$ Use of disease-resistant varieties.
Which of the above are the most effective strategies for managing this disease?

Which of the following is not an objective of Biofortification in crops?

International Rice Research Institute $(IRRI)$ is situated at

In which type of crops is the mass selection method used?