Introduction:
A riverside city is a city that is located on the banks of a river. This geographical feature often plays a significant role in shaping the city's culture, economy, and overall development. In this answer, we will explore why option 'A' is the correct answer and discuss the characteristics of a riverside city.

Geographical Location:
A riverside city is situated along the banks of a river. This means that the city is built in close proximity to the water body, and the river often serves as a defining feature of the city's landscape. The presence of a river provides various advantages and opportunities for the city.

Aesthetic Appeal:
One of the key characteristics of a riverside city is its aesthetic appeal. The river adds natural beauty to the cityscape, creating a picturesque environment. The flowing water, lush greenery, and scenic views attract residents and tourists alike. Many riverside cities take advantage of this natural beauty by developing parks, promenades, and recreational areas along the riverbanks, providing residents with peaceful spaces to relax and enjoy nature.

Water-based Transportation:
Being located on the banks of a river often gives a riverside city access to water-based transportation. Rivers have historically played an essential role in trade and commerce, allowing goods to be transported efficiently. Even in modern times, rivers can still be used for transportation, especially for bulky or heavy goods. This can be advantageous for economic activities and international trade, as it provides an alternative mode of transportation.

Economic Activities:
Riverside cities often have a strong connection to economic activities related to water. Fishing, boating, and water sports are common in these cities, providing livelihoods and recreational opportunities for residents. Additionally, riverside cities may have port facilities, facilitating trade and contributing to the local economy. The river can also attract tourism, with activities such as river cruises and waterfront dining becoming popular attractions.

Cultural Significance:
The presence of a river can have a profound impact on the cultural identity of a city. Rivers are often associated with historical significance, and many riverside cities have a rich heritage and cultural traditions that are closely tied to the river. Festivals, celebrations, and rituals may revolve around the river, creating a sense of community and shared identity among the residents.

Conclusion:
In conclusion, a riverside city is a city located on the banks of a river. Such cities have distinct characteristics, including aesthetic appeal, access to water-based transportation, economic activities related to water, and cultural significance tied to the river. The presence of a river can greatly influence the development and identity of a city, making it an integral part of its overall fabric. Option 'A' correctly describes a riverside city.