A parsec is I. a unit of length used in astronomy II. 2.06 × 10^5 AU III. the distance to an imaginary star whose stellar parallax is one arc second IV. 3.26 light years V. the longest unit of length in astronomy
a. I, II, V b. II, IV
c. I, III, IV, V d. I, II, III, IV, IV
d
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Indicate whether the statement is true or false