[单选题]
According to the second la(ssx0o-ivy g 6xmn- 7jw o/ .*bdu8ub ;oiusz kv)f thermodynamics, for any process that may occur within an isolated system, which onedi.b;u8k )usu/*ovzb of the choices applies?
A. Entropy remains constant.
B. Entropy increases.
C. Entropy decreases.
D. Both A and B are possible.
E. Both A and C are possible.