Question: According to the doctrine of Immaculate Conception, where was Mary when she first become filled with grace?

Is "Roman Catholics believe in the Immaculate Conception of Mary, as proclaimed Ex Cathedra by Pope Pius IX in 1854, namely that she was filled with grace from the very moment of her conception in her mother's womb and preserved from the stain of original sin." the correct answer?
Options are:
+yes.
+no.
yes