Respuesta :

Some clouds are in the troposphere, the lowest layer of the atmosphere. Other clouds are in the stratosphere.  Not all clouds are on the same level. 
a cloud is an aerosol comprising a visible mass of minute liquid droplets, frozen crystals, or particles suspended in the atmosphere above the surface of a planetary body

Clouds are formed in the homosphere (which includes the tropospherestratosphere, and mesosphere). 

hope it helped :)