Answer:
b
Step-by-step explanation:
A dependent clause begins with a subordinating conjunction, which is a form of dependent phrase.
A) The coordinating conjunction 'but' is used to link individual clauses.
B) The subordinating conjunction 'because' begins your dependent clause here.
C) 'In addition,' rather than a conjunction, is a transition expression.
D) The word 'whereas' can also be used as a transition word.