The correct option is
A A large scale air mass that rotates around a strong centre of low atmospheric pressure.
A cyclone is a large scale air mass that rotates around a strong centre of low atmospheric pressure.
The centre of a cyclone is a calm area.
It is called the eye of the storm. It is a
region free of clouds and has light
winds. Around this calm and clear eye, there is a cloud region of
about 150 km in size. In this region
there are high-speed winds (150–250km/h) and thick clouds with heavy
rain. Away from this region the wind
speed gradually decreases.