Answer:
Symbiosis is a close relationship between two species in which at least one species benefits. Mutualism is a symbiotic relationship in which both species benefit. Commensalism is a symbiotic relationship in which one species benefits while the other species is not affected.
 
        
             
        
        
        
The correct option is B, that is, A FAMILY DONATES USED CLOTHING TO A SECOND HAND STORE. 
Waste prevention has to do with the process and practice of reducing the amount of wastes products in order to produce a more sustainable environment. Waste prevention can also be called recycling. There are three types of waste prevention, these are primary, secondary and tertiary waste prevention / recycling. 
Primary waste prevention refers to a situation in which the material to be disposed is not changed in anyway, before been reused. Such material can be given to friend or donated to a charity organization. The material is always used for the same purpose as the original use.  
Secondary waste prevention involves some kind of modifications while tertiary waste prevention usually involves the use of chemicals and heat.  
 
        
                    
             
        
        
        
The Precambrian eon is separated from the Phanerozoic eon in the fossil record because of the sudden appearance of organisms.
Explanation:
Precambrian eon is the initial existence on earth that can be predicted by the study of rocks and remaining of fossils. It has been seen as the existence of skeleton in this era, before this era no such things has been observed, even the development of sexual reproduction. 
The Phanerozoic era comes after the Precambrian era, more advanced kinds of fossils of animals had been observed in this era.  Phanerozoic era period of life on earth. Large organisms sudden appearance are seen in the Phanerozoic era i.e. First dinosaurs, mammals, fishes, angiosperms,first vertebrates etc.
 
        
             
        
        
        
By knocking at the bend of the knee with a small "hammer". If the leg "spasms" then the superficial reflex is in working condition. Hope this helps :)