Answer:
Option A
Explanation:
Options -
A-avoid water pollution.
B-build thermal power plants.
C-add water features to gardens.
D-avoid drip irrigation systems
Solution -
The largest source of freshwater on planet earth is underground water. The water beneath the surface of earth is very limited. The total fresh water reserve on earth is 3% of the total water on earth. Pollution due to discharge of waste water into the rivers and oceans has caused the degradation of not only surface water but also ground water.
Thus, option A is correct
Drip irrigation is a means to prevent wastage of water during irrigation. Thus, avoiding it will cause further loss of fresh water.
Addition of water feature will increase usage of water, thus it is also incorrect
Building thermal plant will also cause water pollution and wastage. Hence, option B is also incorrect
When a specimen is to be observed under the light microscope, scientists usually stain the specimens using different type of chemical stains depending on the type of specimen to be observed. Staining of specimen make the structures that are to be observed in the specimen very visible under the microscope, this make it easy for scientists to observe their structures.
Answer: The cell membrane is selectively permeable.
Explanation: going thru last year notes
Evidence supporting the Big Bang theory includes the presence of cosmic microwave background radiation, visual observation of redshifted objects and the abundance of primordial elements found throughout the universe.