B is unsustainable as this is a practice of intensive farming usually conducted indoors, and is resource and energy expensive. C is unsustainable because groundwater is a limited resource and groundwater can take 1000s of years to be recharged. D is unsustainable as this involves moving water across vast distances and is expensive and ecologically damaging. A is sustainable as drought-resistant plants would in the long run use less water.
Th earth scientists have improved our understanding with the environment because of their studies in which they had shown better understanding and explanation of occurrences with the means of having to provide not only explanation nor visuals but also providing proof of these mere existence that made people believe and understand the environment.
I n the F1 generation, there will be no recessive offspring but in the F2 generation there is a 25% of offspring being recessive.
You can find more info about percentages by observing images. called Punnett Squares.
Hope it helped,
BioTeacher101
