He built a(n) _____ to his house for his new sauna, but the room addition cost so much by the time it was finished, he couldn't afford the sauna.

Which word BEST COMPLETES this sentence?
The DUPLEX expanded because of this.
  1. CORNERSTONE
  2. PALLOR
  3. ANNEX
  4. HAPHAZARD
  5. CLEAVE
A B C D E
1/20 SAVE