Which one of the following is an improved variety of maize?

In maize,hybrid vigour is exploited by

Fill in the blanks in the following statements ($A$ to $C$):
$(A)$ The capacity to generate a whole plant from any cell/explant is called ......$(i)$ .......
$(B)$ The transfer of resistance genes occurs through ........$(ii)$........ . Subsequently,........$(iii)$ ....... occurs between the target and the plant source.
$(C)$ The rice variety $IR8$ was developed in the country ........$(iv)$ ........

What is meant by germplasm collection? What are its benefits?

Which method is used to develop all the cultivated varieties of sugarcane?

Varieties developed by the pureline method are