If x^a mod n = c and x^b mod n = d then x^a+b mod equals

A. c + d mod n

B. c*d mod n

C. c^d mod n

D. None of the above

If c = x mod n then c is guaranteed to be in which of the following sets

A: { 1, 2, 3, n-1 }

B: { 0, 1, 2, 3, . n-1 }

C: { -(n-1), -(n-2), -(n-3), -2, -1 0 }

D: { 1, 2, 3, . n }

Which of the following statement(s) are true.

a: P is contained in NP. b: All solvable problems are in P.

c: The traveling salesman problem is in NP. d:The traveling salesman problem is not solvable.

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A: a b c

B: a c

C: a c d

D: a, d