Question: Which American multinational oil field service company has been testified against in Congress by Bunny Greenhouse in 2005?
Sentence (from "Bunny Greenhouse"): On June 27, 2005, she testified to a Congressional panel, alleging specific instances of waste, fraud, and other abuses and irregularities by Halliburton with regard to its operations in Iraq since the 2003 invasion.
Relevant evidence: Yes