Select the phrase that the reader understand the word argument as it is used in the sentence. because she was so upsethighlighted: because she was so upset and speaking unclearlynot highlighted: speaking unclearly, it was very difficult to follownot highlighted: very difficult to follow my little sister’snot highlighted: my little sister’s argument and understand how she had reached her conclusionnot highlighted: how she had reached her conclusion.

How she had reached her conclusion.

Explanation:

The word 'argument' implies the act of exchanging some form of differing opinions or diverging ideas about something or anything. It usually turns into a heated conversation, a loud and sometimes even violent discussion.

In the given sentence, the use of the word argument can best be understood when the speaker talks of "how she had reached her conclusion". Without this, it is quite unclear to understand what the argument meant, for "it was very difficult to follow" what the main issue was. But, with the ending phrase "how she had reached her conclusion", the readers can know and understand the use of the word "argument" in the sentence.