• Original sentence: I usually drive to work, but today I go by bus.
• Options:
  • A. Although I can drive to work, I go by bus today. (Correct)
  • B. Although I can go by bus, I drive to work today. (Incorrect)
  • C. Instead of driving to work, I go by bus today. (Correct)
  • D. Instead of going by bus, I drive to work today. (Incorrect)

Explanation:

• The sentence expresses a contrast between the usual action and the current action.
• "Although" and "instead of" can both be used to express contrast.
• Option A correctly expresses the contrast using "although."
• Option C correctly expresses the contrast using "instead of."