Which was the last human chromosome to be completely sequenced ?

Options

A. Chromosome 1
B. Chromosome 11
C. Chromosome 21
D. Chromosome-X

Explanation

**Step-by-Step Solution:**

1. **Understanding Human Chromosomes**: Humans have a total of 23 pairs of chromosomes, which means there are 46 chromosomes in total. Each chromosome carries genetic information.

2. **Identifying the Question**: The question asks for the last human chromosome to be completely sequenced. This refers to the completion of the sequencing process of the DNA within that chromosome.

3. **Human Genome Project (HGP)**: The Human Genome Project was an international scientific research project aimed at mapping and understanding all the genes of the human species. It began in the early 1990s and was completed in the early 2000s.

4. **Sequencing of Chromosomes**: Throughout the Human Genome Project, various chromosomes were sequenced. The sequencing of chromosomes occurred in stages, and some chromosomes were completed before others.

5. **Identifying the Last Chromosome**: The last human chromosome to be completely sequenced was Chromosome 1. It was sequenced approximately two decades after the Human Genome Project began.

6. **Conclusion**: Therefore, the answer to the question is Chromosome 1, which is also the largest human chromosome.

**Final Answer**: The last human chromosome to be completely sequenced was Chromosome 1.

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