Rita Owns an Art Business Called Rita's Art Works

Rita owns an art business called Rita's Art Works. Rita receives a commission to paint a mural on the side of a building downtown. Three of Rita's employees are painting the mural on the building when the scaffold they erected to do the project falls and injures a passerby. Later it was found that the passerby was drunk and accidentally stumbled into the scaffolding causing it to fall. If the passer by sues Rita for negligence, she can avoid liability by using the defense of:

A) self protection.
B) lack of intent to harm.
C) assumption of risk.
D) contributory negligence.