How many grams of potassium chlorate decompose

How many grams of potassium chlorate, KClO3 decompose to form potassium chloride and 250.0 mL of O2 at 127˚C and 0.850 atm of oxygen? Molar Mass (KClO3) = 122.55 g/mol

KClO3 (s) + KCl (s) + O2 (g)

a. 0.00647 g
b. 0.529 g
c. 0.735 g
d. 1.19 g
e. 4.76 g