I cannot understand very well
I have a puzzle about a short text:
A mother and son washing dishes while father and daughter were watching TV, suddenly, a dish droped down, and there was complete silence.
The girl looked at her father and said,"It was Mom."
"How do you know?" asked her father.
"She didn't say anything."
So How to explain the sentence"asked her father". From the whole text, it means father ask her daughter, but i am not sure how the "asked" used,it just represent the past tense? or other meanning?