In the 113th Congress (2013-2015), Bills Supported by President Barack

In the 113th Congress (2013-2015) , bills supported by President Barack Obama were passed in the Senate 93 percent of the time and in the House only 15 percent of the time.What was the most important factor behind this outcome?

A) Obama failed to hire legislative staff who could work with House members.
B) Vice President Joe Biden, being a former senator, expertly shepherded bills through the Senate in a way that no one in the administration could in the House.
C) The Senate was controlled by fellow Democrats, while the House was controlled by Republicans.
D) The Republicans had more coordinated and effective leadership in the House than in the Senate, despite controlling both chambers.