Which of the following statements is/are true? You may select one, more than one, or none of the options.

a) *delta* Ssurr = 0 for a reversible process

b) *delta* S = 0 for a reversible process

c) *delta* S= 0 for an adiabatic process

d) *delta* Suniv = 0 for an adiabatic process

e) *delta* Suniv= 0 for a reversible process

f) *delta* Ssurr = 0 for an adiabatic process