Which of the listed rivers has the greatest length?

Analysis:

The question asks to identify the river with the greatest length from the given options.

The options are:

1. 1) Mississippi
2. 2) Ob
3. 3) Volga
4. 4) Amazon

We need to compare the lengths of these rivers:

• Mississippi River (USA): Approximately 3,766 km (including Missouri). The Mississippi River itself is about 2,320 km.
• Ob River (Russia): Approximately 3,650 km.
• Volga River (Russia): Approximately 3,530 km.
• Amazon River (South America): Approximately 6,992 km. It is widely considered the longest river in the world.

Comparing these lengths, the Amazon River is significantly longer than the others.

Answer: 4