Answer :
D.
The two parts are independent of each other, which dictates the use of a semicolon. "Traffic was heavy." and "We were late."
"Consequently" is a transition between the two, and requires a comma.
The two parts are independent of each other, which dictates the use of a semicolon. "Traffic was heavy." and "We were late."
"Consequently" is a transition between the two, and requires a comma.