vs
QUICK ANSWER
"El" is a form of "el", a definite article which is often translated as "the". "Lo cual" is a phrase which is often translated as "which". Learn more about the difference between "lo cual" and "el" below.
lo cual(
loh
kwahl
)A phrase is a group of words commonly used together (e.g., once upon a time).
el(
ehl
)A definite article is a word that identifies a noun as specific or known to the speaker (e.g., the girl).