Monseigneur, the Bishop is a-ahem!

Monseigneur, the Bishop is a-ahem!
(a) Why does Persome not complete the sentence?
(b) Why is she angry with the Bishop?
© The word ‘ahem’ used in the extract is…

(a) Persome did not complete the sentence because she did not wish to criticise the Bishop in front of Marie.
(b) She is angry with the Bishop because he has sold her silver salt-cellars.
© a short coughing sound made to avoid saying something embarrassing