When an occlusion occurs,
options:
the cold front overtakes the warm front and the warmer air is lifted from the surface.
the cold front overtakes the warm front and the colder air is lifted from the surface.
the warm front overtakes the cold front and the colder air is lifted from the surface.
the warm front overtakes the cold front and the warmer air is lifted from the surface.

Option (1)

Explanation: In an occluded front, the cold air overtakes or completely replaces the warm air in the atmosphere. It generally forms at the region where the atmospheric pressure is relatively low.

Due to the presence of an occluded front, the direction of wind and the temperature varies i.e the temperature could be high or low and the wind may be strong or weak. in addition to that there might be occurrence of a heavy rainfall as well as thunderstorms.

Thus the correct answer is option (1).