challenge: What does Senate Class 1 indicate about a senator's term in the 82nd United States Congress?
  
  A. Their term ends with this Congress and they face re-election in 1952
  B. Their term began in this Congress and they face re-election in 1956
  C. Their term began in the last Congress and they face re-election in 1954
  D. Their term began in the previous Congress and they face re-election in 1950
  Answer: 