Answer:
The correct answer will be option-formation of heterochromatin
Explanation:
Methylation of DNA is the epigenetic mechanism which controls the expression of a gene by adding a methyl group to the cytosine bases in eukaryotic DNA.
The methylation of DNA converts the cytosine residues to the  5-methylcytosine catalysed by DNA methyltransferase enzyme. This results in the silencing of the gene and transcription get switched off.
Studies have shown that DNA methylation is involved in the formation and maintenance of the heterochromatin structure which is the condensed form of the chromatin in which transcription is switched off.
Thus, the formation of heterochromatin is the correct answer.
 
        
             
        
        
        
Answer: Solution in Water
Explanation:
I believe this refers to the reaction between Zinc and Hydrochloric acid. 
When this happens, the solution will be Zinc Chloride but as it happened in a solution (the acid), the resulting Zinc Chloride salt would be in aqueous form which means that it would be a solution in water which is the other product of this reaction.
Had the zinc reacted with gaseous HCI, it would have resulted in a Zinc Chloride with no liquid in it. 
 
        
             
        
        
        
Answer:
The answer would be A
Explanation:
I took the test last year
 
        
             
        
        
        
Answer:
Commensalism
Explanation:
Commensalism is when one organism benefits and the other doesn't benefit and is also not harmed. The tree is helping the orchid and the orchid isn't benefiting or harming the tree.
 
        
             
        
        
        
The answer is A. Plantae
Plantae is a multi cellular organisms which produce their food from photosynthesis , Sunflower is one of them. They're also known as metaphyta,
Hope this helps