Sulfur Dioxide Reacts with Chlorine to Produce Thionyl Chloride (Used $\to$

Sulfur dioxide reacts with chlorine to produce thionyl chloride (used as a drying agent for inorganic halides) and dichlorine oxide (used as a bleach for wood, pulp, and textiles) . SO₂(g) + 2Cl₂(g) $\to$ SOCl₂(g) + Cl₂O(g)
If 0.400 mol of Cl₂ reacts with excess SO₂, how many moles of Cl₂O are formed?

A) 0.800 mol
B) 0.400 mol
C) 0.200 mol
D) 0.100 mol
E) 0.0500 mol