What was deposited on the bottom of the gas bottle

A．The hydrochloric acid broke the carbon bonds in the carbon dioxide.
B．The magnesium oxide broke the carbon oxygen bonds in the carbon dioxide.
C．The burning magnesium broke the carbon oxygen bonds in the carbon dioxide.
D．The gas collection method broke the carbon-oxygen bonds in the carbon dioxid

A．That Bob does not get along with his lab partner.
B．That the students performed the experiment correctly.
C．That the students had problems, and could not complete the lab experiment.
D．That there was a fire in the lab during the experiment.