What is an oratorio?

2 points
An aria within an opera
Sacred (Bible) text set to music
An elaborate stage show
A madrigal

An oratorio is a sacred (Bible) text set to music.

is this right?

Yes, that is correct. An oratorio is a large-scale musical work for orchestra and voices, typically based on a religious theme and often performed in a concert setting rather than as part of a theatrical production.