Genetic information is carried out by long chain molecule made up of nucleotides.

Introduction:
Genetic information is the set of instructions that determine the characteristics and traits of an organism. This information is stored in the form of a long chain molecule called DNA (deoxyribonucleic acid) or RNA (ribonucleic acid). These molecules are made up of smaller subunits called nucleotides.

Nucleotides:
Nucleotides are the building blocks of DNA and RNA. Each nucleotide consists of three main components: a nitrogenous base, a sugar molecule, and a phosphate group. The nitrogenous base can be adenine (A), thymine (T), cytosine (C), and guanine (G) in DNA, while in RNA, thymine is replaced by uracil (U). The sugar molecule in DNA is deoxyribose, whereas in RNA, it is ribose. The phosphate group connects the nucleotides together to form a long chain.

Formation of DNA:
In DNA, the nucleotides are joined together through phosphodiester bonds between the phosphate group of one nucleotide and the sugar molecule of the next nucleotide. This forms a sugar-phosphate backbone. The nitrogenous bases extend from the backbone and pair up with complementary bases on the opposite strand. Adenine always pairs with thymine (or uracil in RNA) through two hydrogen bonds, while cytosine always pairs with guanine through three hydrogen bonds. This base pairing allows for the replication and transmission of genetic information.

Genetic Code:
The sequence of nucleotides in DNA or RNA determines the genetic code. The genetic code is a set of rules that specifies the correspondence between a specific sequence of nucleotides and the amino acids that make up proteins. Proteins are essential for the structure, function, and regulation of cells and organisms.

Conclusion:
In summary, genetic information is carried out by long chain molecules made up of nucleotides. These nucleotides form the DNA or RNA, which store and transmit the genetic instructions for the development, functioning, and characteristics of an organism. The sequence of nucleotides in DNA or RNA determines the genetic code, which is responsible for the synthesis of proteins.

DNA is a polymer made from four different monomers , called nucleotides so option A is correct