I think the correct answer from the choices listed above is option A. When crossing-over takes place, chromosomes exchange corresponding segments of DNA. Corresponding genes on non-sister chromatids are exchanged at chiasmata. Hope this answers the question.
they need energy because growth is not the only life process that requires energy.Apart from growth, when organism reaches adulthood they need energy to aid in other processes such as locomotion,reproduction. More also, important functions such as cell replacement requires energy.
Ewaste is a problem because it contains many hazardous chemicals like mercury, lead and cadmium which could seep in to the soil and eventually to the groundwater. This would lead to contamination of the drinking water. The most important thing to remember would be to separate this type of waste with the others. It would be better if you sell it or give it for reuse. Also, you can send it to a recycler that knows what to do with these wastes.