Which type of sugar is present in DNA and RNA?

The correct answer is Option (2) → Pentose sugar.

DNA and RNA are both polynucleotides. Each nucleotide has three parts: a nitrogenous base, a sugar and a phosphate group. The sugar has five carbon atoms, so it is a pentose. In RNA this pentose is ribose, and in DNA it is deoxyribose. Hexoses (six carbons), heptoses (seven) and tetroses (four) are not the sugars of nucleic acids.

NCERT Extract:
Structure of Polynucleotide Chain – “Let us recapitulate the chemical structure of a polynucleotide chain (DNA or RNA). A nucleotide has three components – a nitrogenous base, a pentose sugar (ribose in case of RNA, and deoxyribose for DNA), and a phosphate group. There are two types of nitrogenous bases – Purines (Adenine and Guanine), and Pyrimidines (Cytosine, Uracil and Thymine). Cytosine is common for both DNA and RNA and Thymine is present in DNA. Uracil is present in RNA at the place of Thymine.”