Answer:
The correct answer would be B) The complementary base pair rules. 
DNA serves as the genetic material in most of the living organisms and is transmitted from parents to their offspring. 
It is like blue print of the cell which contains all the necessary information required for the functioning and regulation of cell in the form of nucleotide sequences.
Generally, DNA consists of two strands which are complementary in nature i.e. purine base pair with its specific pyrimidine (adenine always base pair with thymine and guanine always base pair with cytosine).
This property of DNA is of utmost importance in the process of DNA replication as daughter DNA strand is formed on the basis of complementary base pair of the template strand.
It ensures that correct DNA sequence is produced for transmission to the offspring or daughter cell.
 
        
             
        
        
        
Some parts of the ocean never receive sunlight.
Answer: true
        
             
        
        
        
Answer:
The correct answer is option D. "preservation of wetlands".
Explanation:
Wetland are areas of lands that are saturated with water, usually comprised by marshes or swamps. Preservation of wetlands help to reduce the risk of floods because wetlands temporarily store and slow the release of stormwater. It has been reported that areas where wetland have been lost, the chances of flood increases by as much as 80 percent. The government of a flood-prone region would likely reduce the risk of floods by preserving its wetlands.
 
        
             
        
        
        
<span>Yes,
there are mammals that lay eggs instead of giving birth to a live young. These mammals
are called Monotremes. One best example to this is the platypus and echidnas.
Platypus, which is also known as the duck-billed platypus, is a semiaquatic
egg laying mammal. Echidnas on the other hand are also called as spiny eaters.
Echidna and platypus are only the surviving members of the Tachyglosside. And are
the sole extant egg laying mammal</span>