Which one of the following is applicable to collision-coalescence proc

Which one of the following is applicable to collision-coalescence process of precipitation?

Clouds which do not extend beyond the freezing level
Clouds which extend beyond the freezing level
All types of clouds
Cirrocumulus cloud
This question was previously asked in
UPSC CDS-1 – 2018
The collision-coalescence process is a mechanism of rain formation that is most effective in warm clouds, i.e., clouds where the temperature is above freezing (0°C) throughout. In these clouds, larger cloud droplets fall and collide with smaller droplets, merging with them (coalescing). As they collect more droplets, they grow larger until they become heavy enough to fall as raindrops. This process does not require ice crystals.
The collision-coalescence process is the primary mechanism for precipitation in warm clouds (not extending beyond the freezing level).
Clouds that extend beyond the freezing level often involve the ice crystal process (Bergeron-Findeisen process), where supercooled water droplets evaporate and deposit water vapor onto ice crystals, which then grow and fall as snow or melt into rain. Cirrocumulus clouds are high-altitude ice clouds.