The following reaction is often used to produce H₂SO₄ :
SO₃ + H₂O --> H₂SO₄
In one experiment a student reacted a certain amount of SO₃ with excess H₂O to produce H₂SO₄ . The student calculated the theoretical yield of H₂SO₄ from this reaction to be 196.0 g . However, at the end of the reaction , the actual yield of H₂SO₄ was measured to be 127.4 g .

What was the percent yield of this reaction ?
a. 60.0%
b. 0.65%
c. 6.50%
d. 65.0%