Questions

Choice 1 is correct as it matches with the flow of the passage. The whole paragraph is about the devastating effects that nuclear weapons have due to certain curtailments on part of the
scientists in the moral and the conscience aspect. It is only logical to mention an argument to support the next statement. It also keeps up with the tone and general
subject of the passage.
Option 2 is a bad choice as it talks about absolutely nothing and is too naïve. Therefore is incorrect as it is beyond the general theme.
Option 3 is incorrect as it obviously does not go with the flow of the Para.
As for option 4, it is incorrect as the statement is illogical.
As for 5, neither does it logically follow the previous sentence nor is it related to the anything in the next sentence.

Aldosterone is a key steroid hormone critical for maintaining salt and water balance. It regulates the concentration of minerals, like sodium and potassium, in the fluid outside your cells. When your sodium levels drop, or potassium levels rise, your body signals your adrenal glands to release aldosterone into your blood. Aldosterone signals your kidneys to reabsorb sodium into the blood, and acts on your sweat glands to reduce sodium loss through sweat.

The Chipko movement. In the 1970s, an organized resistance to the destruction of forests spread throughout India and came to be known as the Chipko movement. The name of the movement comes from the word 'embrace', as the villagers hugged the trees, and prevented the contractors' from felling them.