Option C will not compile; the synchronized modifier applies only to methods.

Option A and B will compile because protected and transient are legal variable modifiers. Option D will compile because volatile is a proper variable modifier.

The private access modifier limits access to members of the same class.

Option A, B, D, and E are wrong because protected are the wrong access modifiers, and final, static, and volatile are modifiers but not access modifiers.

(A) is valid interface declarations.

(B) and (C) are incorrect because interface variables cannot be either protected or transient. (D) is incorrect because interface methods cannot be final or static.