Definition: In this task, you will use your knowledge about language (and common sense) to determine what element the marked number refers to. The numbers are marked with two underlines around them, like: _ number _. Your answer should be chosen from the given text, and should not contain other words.
Input: Maxwell Smart:  Three months ago we had an open and shut case against Mondebello . Not only would he have gone to the electric chair , but he would have lost his booking franchise besides . Unfortunately , just before the trial , our key witness was murdered .
Ann Ferris: Were you on that case , Mr. Smart ?
Maxwell Smart: No , the Chief bungled that _ one _ himself .

case