Select the sentence that is punctuated correctly. (Points : 1)

Sitting in the medical office waiting room, Veronica smiled nervously at the woman sitting next to her, but then she had to get up suddenly because the receptionist summoned her to the window.
Sitting in the medical office waiting room, Veronica smiled nervously at the woman sitting next to her, but then she had to get up suddenly because, the receptionist summoned her to the window.
Sitting in the medical office waiting room Veronica smiled nervously at the woman sitting next to her, but then she had to get up suddenly, because the receptionist summoned her to the window.

What do you think?

Sitting in the medical office waiting room, Veronica smiled nervously at the woman sitting next to her, but then she had to get up suddenly because the receptionist summoned her to the window.

The correct sentence is:

"Sitting in the medical office waiting room, Veronica smiled nervously at the woman sitting next to her, but then she had to get up suddenly because the receptionist summoned her to the window."

To determine the correct answer, we need to look at the punctuation in each sentence. The first option uses correct punctuation with the use of commas to separate the different clauses in the sentence. The second option incorrectly places a comma before "the receptionist summoned her to the window." The third option incorrectly places a comma after "suddenly."