Before Walter was freed, how many people had been exonerated from death row since 1976?

D. 49

From the text:

In 1992, the year before Walter’s release, thirty-eight people were executed in the United States. This was the highest number of execu- tions in a single year since the beginning of the modern death penalty era in 1976. That number rose to ninety-eight in 1999. Walter’s release coincided with increased media interest in the death penalty, triggered by the increasing pace of executions. His story was a counternarrative to the rhetoric of fairness and reliability offered by politicians and law enforcement officials who wanted more and faster executions. Wal- ters case complicated the debate in very graphic ways.

The Death Penalty Information Center reported that Walter was the fiftieth person to be exonerated in the modern era.