The correct answer is option 'A', the Buckingham Canal.

The Buckingham Canal is a man-made waterway that runs through much of Andhra Pradesh and ends in northern Tamil Nadu. It was constructed during the British colonial period in the 19th century and was initially used for irrigation and transportation purposes.

Here is a detailed explanation of the answer:

1. The Buckingham Canal:
The Buckingham Canal is a 800 km long man-made waterway that stretches from Peddaganjam in Krishna district of Andhra Pradesh to Marakkanam in Viluppuram district of Tamil Nadu. It was named after the then Governor of Madras Presidency, the Duke of Buckingham and Chandos. The canal was constructed to connect the Krishna and Godavari rivers in Andhra Pradesh to the Palar River in Tamil Nadu.

2. Geographical Significance:
The Buckingham Canal is a significant waterway in the region as it passes through several major cities and towns, including Chennai, Nellore, Vijayawada, and Machilipatnam. It serves as a vital link for irrigation, transportation, and water supply to the surrounding areas.

3. Historical Importance:
The canal was initially built for irrigation purposes to facilitate the transportation of goods and agricultural produce. It played a key role in the economic development of the region during the British era. However, with the advent of railways and improved road networks, the canal lost its importance as a major transportation route.

4. Present-day Scenario:
Today, the Buckingham Canal is not extensively used for transportation but is still utilized for irrigation purposes. It also serves as a source of drinking water for several towns and villages along its course. The canal is a popular tourist attraction, with stretches of the canal being developed for boating and recreational activities.

In conclusion, the Buckingham Canal is the waterway that runs through much of Andhra Pradesh and ends in northern Tamil Nadu. It has historical significance and continues to serve as an important water source for irrigation and drinking water purposes in the region.