Which component of air is the primary problem in a condition known as "the bends"?

a. He

b. CO

c. O2

d. N2

e. CO2

d. N₂

Explanation:

Bends -

As the scuba divers go deep inside the sea the pressure deep inside the sea is very high, and during this high pressure, number of gases (specially nitrogen gas) get dissolved in the blood vessels.

And, as soon as the divers comes back to the surface, the pressure gets back to normal, i. e., reduces, and hence, the dissolved gases tries to escape out by causing bubbles of nitrogen gas, which is very painful and can lead to low back pain, numb legs, weakness in body, vomiting, dizziness and can be fatal.

Hence, to avoid the condition of bends, the gas cylinder of divers are flushed with diluted air containing 11.7% helium, 56.2% nitrogen and 32.1% oxygen.