The neuter relative pronoun Lo que and Lo cual

Question

SpanishDict says.

Lo cual can only be used to refer to something that has already been mentioned in the same sentence.

Lo que can be used any time lo cual is used, and it can also be used to refer to something that has not been brought up before in the same sentence.

However the practice quiz at the bottom say

Lo cual is best for the sentence since it refers to an antecedent specifically mentioned earlier in the phrase

when i chose lo que as the answer as in the following example:

El niño gritó en voz alta, lo cual me molestó mucho.The child screamed in a loud voice, which upset me very much.

My question is, Should i adapt the definition? In which case the sentence above becomes,

El niño gritó en voz alta, lo que / lo cual me molestó mucho.

Or should I use lo cual over lo que whenever something is mentioned before

Answer 1

Both "lo que" and "lo cual" are fine as equivalents of the sentence relative "which".

It is true that "lo cual" is a stronger linker and may sound slightly better than "lo que" in those contexts.

The other definition, of "lo que" being equivalent to nominal relative "what", is also correct:

• Lo que me molestó mucho es que el niño gritara en voz alta. (What annoyed me terribly was that the boy should shout so loudly.)

In the sentence above, "lo cual" is ungrammatical.