Which of the following is wrong about clouds?

a) One of the Cloud disadvantages is Internet reliabilitywhich must be considered as risk

b) Mostexpensive cloud is the private because the full service is paid by the customer.

c) Cloud is the model in which customers use servicrs on the cloud and need air plane to reach it.

d) One advantage of cloud computing is ability to decrease the cloud services in low business time

e) Cloud environment can be public, private and community or combination of them.