<span>The bottleneck effect is the cause of the sudden shift in the genetic information of the population. Due to the landslide, suddenly high number of the members of the main population died, and this caused genetic drift for reducing the variation in the existing generation, which is now widely different from the original one.</span><span />
        
             
        
        
        
By performing this dance, successful foragers can share, with other members of the colony<span>, information about the direction and distance to patches of flowers yielding nectar and pollen, to water sources, or to new nest-site locations.</span>
        
             
        
        
        
A solution that has a pH of 6.8
it is <em>acidic</em><em> </em>as it has got ph value less than 7....But as it has got ph value near to 7 it is weak acidic..
 
        
             
        
        
        
The correct answers are:
Viruses are bundles of genetic material enclosed in a capsid.<span>
</span>Viruses are not living, so D is incorrect. 
Viruses are much smaller than bacteria, so A is incorrect.