The answer is B. Because, The correct match is like this : Adenine-Thymine and Guanine-Cytosine. A-T and G-C
The tRNA molecule determines the type of amino acid!
Regulation of HMG-CoA reductase is termed as the rate of controlling enzyme of the mevalonate pathway which produces other isoprenoid and cholesterol.
The regulation of cholesterol is done by regulating the rate which determines step catalyzed by HGM -CoA reductase.
There is long-term and short-term regulation where HGM-CoA is inhibited by phosphorylation and catalyzed of proteins. There is regulated proteolysis of HGM-CoA reductase where degradation of HMG-CoA reductase by oxidized derivatives of cholesterol.