Question

The total number of nitrogenous bases in human genome is estimated to be about

• A. 3.5 million
• B. 35 thousand
• C. 35 million
• D. 3.1 billion

Answer 1

Answer: (D)

3.1 billion

Answer 2

Each region of DNA that codes for a single RNA or protein is called a gene and the entire set of genes in a cell, organelle or virus form it's genome. Human genome project, launched in $1990$ is a world wide effort to map to positions and to sequence all the DNA base pairs of the human genome, which are 3 billion $3 \times 10^{9}$ base pairs. So, the option $d$ is nearest.