Select the option that expresses the given sentence in passive voice.
The invigilator is advising the students not to carry calculators into the examination hall.

A

The students were advised not to carry calculators into the examination hall.

B

The students are being advised by the invigilator not to carry calculators into the examination hall.

C

The students have been advised not to carry calculators into the examination hall by the invigilator.

D

The students were advised the invigilator not to carry calculators into the examination hall.