Which answer choice demonstrates the best way to combine the following sentences? The oranges have been sitting on the table for a week. They are starting to look brown.

A. The oranges, which have been sitting on the table for a week, are starting to look brown.

B. The oranges which have been sitting on the table for a week are starting to look brown.

C. For a week the oranges have been on the table sitting, which are starting to look brown.