How many of the following statements regarding thermal pollution are INCORRECT ?
a. Heated wastewaters flowing out of electricity-generating units , e.g., thermal power plants , constituent an important category of pollutants.
b. Thermal wastewater eliminates or reduces the number of orgenisms sensitive to high temperatures.
c. It may enhance the growth of plants and fish in extremely cold areas but. Only after causing damage to the indigenous flora and fauna.
d. Thermal wastewater increases the number of orgenisms sensitive to high temperatures.

Options

A. four
B. two
C. three
D. one

Answer

To determine how many of the statements regarding thermal pollution are incorrect, let's analyze each statement one by one:

### Step 1: Analyze Statement A
**Statement A:** "Heated wastewaters flowing out of electricity-generating units, e.g., thermal power plants, constitute an important category of pollutants."

**Analysis:** This statement is correct. Heated wastewater from thermal power plants is indeed a significant pollutant as it raises the temperature of water bodies, affecting aquatic life.

**Hint:** Consider what constitutes a pollutant. Heat can be a pollutant, not just chemicals.

### Step 2: Analyze Statement B
**Statement B:** "Thermal wastewater eliminates or reduces the number of organisms sensitive to high temperatures."

**Analysis:** This statement is also correct. When thermal wastewater is introduced into a water body, it raises the temperature, which can lead to the decline of organisms that cannot tolerate higher temperatures.

**Hint:** Think about how temperature affects the survival of species in aquatic ecosystems.

### Step 3: Analyze Statement C
**Statement C:** "It may enhance the growth of plants and fish in extremely cold areas but only after causing damage to the indigenous flora and fauna."

**Analysis:** This statement is correct. While thermal pollution can increase the growth of certain species in cold areas by raising the temperature, it can also harm the existing cold-adapted species, leading to a loss of biodiversity.

**Hint:** Consider the balance between new growth and the impact on existing species.

### Step 4: Analyze Statement D
**Statement D:** "Thermal wastewater increases the number of organisms sensitive to high temperatures."

**Analysis:** This statement is incorrect. If organisms are sensitive to high temperatures, an increase in temperature due to thermal wastewater would lead to a decline in their numbers, not an increase.

**Hint:** Reflect on the relationship between temperature sensitivity and population dynamics.

### Conclusion
After analyzing all four statements, we find that:
- Statements A, B, and C are correct.
- Statement D is incorrect.

Thus, the number of incorrect statements regarding thermal pollution is **1**.

### Final Answer
**1 statement is incorrect.**