Question

1. one significant environmental threat to european rivers today is:

a. total desertification
b. isolation from other water systems
c. industrial pollution
d. lack of navigable routes

Explanation:

• Option a: Desertification is land - related, not a direct threat to rivers.
• Option b: European rivers are connected to other water systems, and isolation is not a major threat.
• Option c: Industrial activities release pollutants like chemicals, heavy metals, etc. into rivers, which is a significant environmental threat to European rivers.
• Option d: Lack of navigable routes is a transportation - related issue, not an environmental threat to the river ecosystem.

Answer:

c. Industrial pollution