The bottom line is the minimum condition or limit that must be adhered to. Everything in the world has a bottom line. Crossing the bottom line means qualitative change. If you don't pay attention to the bottom line, you're driving yourself into a desperate situation.
According to the above definition, which of the following situations is crossing the bottom line?
Wang, a lawyer at Hongda Law Firm, lost the key evidence of a major case, which resulted in the acquittal of the suspect and caused great social impact.