DrFaber Explained to Her Students That Holding a Pen in Their

Dr.Faber explained to her students that holding a pen in their teeth would make them feel happier.What is the main reason for this phenomenon?

A) Holding a pen in your teeth sends emotion signals to the pleasure center in the brain.
B) Holding a pen in your teeth contracts the muscles of the face in the same way as a smile.
C) Feeling silly with a pen in your mouth causes you to feel happier.
D) Seeing others' reactions to the pen in your mouth causes you to feel happier.