True or false:

the class np contains some problems that can be solved in polynomial time.
all of the problems in np can be solved in worst-case exponential time.
there are problems that can be reduced to the hamiltonian circuit problem and for which we have polynomial-time algorithms.
there are problems that the hamiltonian circuit problem can be reduced to and for which we have polynomial-time algorithms.

answer; /// i believe the correct answer is (color filter);

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