The term "vitamin" was coined by

Which of the following statements is false?

What does $pH$ stand for?

$A$: Variations exist among different species of living organisms.
$R$: The sequence,type,and number of amino acids in the structure of a protein are fixed.

Match List $-I$ with List $-II$.

List $-I$ (Biological Molecules)	List $-II$ (Biological functions)
$(a)$ Glycogen	$(i)$ Hormone
$(b)$ Globulin	$(ii)$ Biocatalyst
$(c)$ Steroids	$(iii)$ Antibody
$(d)$ Thrombin	$(iv)$ Storage product

Choose the correct answer from the options given below:

Refer to the given structure of adenylic acid. In this,identify $A$.