This nitrogenous base, adenine, pairs with in dna. a) adenine b) cytosine c) guanine d) thymine

The right option is; D) thymine

This nitrogenous base, adenine, pairs with thymine

Nitrogenous bases are organic molecules that contain nitrogen and possess similar chemical properties of a base. There are various nitrogenous bases but the five most important ones that are located in DNA and RNA are adenine, guanine, cytosine, thymine, and uracil. Each of these bases has a complementary base that it pairs with to form DNA and RNA. The complementary base of adenine is thymine i.e adenine pairs with thymine to form DNA and RNA.

halogen, any of the six nonmetallic elements that constitute group 17 (group viia) of the periodic table. the halogen elements are fluorine (f), chlorine (cl), bromine (br), iodine (i), astatine (at), and tennessine (ts).

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."