How does the use of an informal writing style best help
readers understand the topic?

It helps readers find the exact location of a black hole.

It helps readers visualize the inside of a black hole in
space.

It helps readers learn new black hole names and
phrases.

It helps readers understand how far away black holes
are located

It helps the writers visualize the inside of a black hole.

The other options can described bluntly and scientifically with just names and numbers.

If the writer were to use more formal writing to describe things so abstract like a black hole, it would be hard for the common reader to understand.

for example,

The black hole looks like a giant vacuum of nothingness (informal)

The black hole is like a mass whose Schwarzchild radius is outside of itself (formal)

Which is easier to understand? Most likely the first one because of the use of informal language and writing.

Hope I helped!

what do u need with

roses are red,

violets are black,

for what you said,

i hope you sit on a big fat tack.