Question

Bill and Lydia paid their rent regularly and on time. Therefore, they were surprised to find a notice about the late payment of their rent in the mail.
Which option best combines the two sentences? [Advanced]

• A. Bill and Lydia paid their rent regularly and on time, so they were surprised to find a notice about the late payment of their rent in the mail.
• B. Bill and Lydia paid their rent regularly and on time, and they were surprised to find a notice about the late payment of their rent in the mail.
• C. Paying their rent regularly and on time, Bill and Lydia were surprised to find a notice about the late payment of their rent in the mail.
• D. NO CHANGE

Answer 1

The correct option is A Bill and Lydia paid their rent regularly and on time, so they were surprised to find a notice about the late payment of their rent in the mail.

Since the first sentence is stated as a reason for the second, a conjunction substitute of "therefore" must be used to express the cause-effect relation. Hence, Option A is correct. The rest of the options do not express the cause-effect relation, hence these are incorrect.