Explain what the narrator means when she writes that she “felt the apertures of my ears distend.”

It means a natural opening in something or become wider

It is an example of creative idioms

So what are idioms mean?

An idiom is a phrase or expression that typically presents a figurative, non-literal meaning attached to the phrase; but some phrases become figurative idioms while retaining the literal meaning of the phrase. Categorized as formulaic language, an idiom's figurative meaning is different from the literal meaning

there mad at that place

the answer that is correct is the last option.