A ${\color{Red}{\text{board}}}$ is a planed piece of wood, a ruling body for some organizations, or a verb that means to get in or on a form of transportation, such as a plane or ship.
The homonym ${\color{Purple}{\text{bored}}}$ is an adjective that means to feel restless or antsy as a result of lack of activity or interest in current activity.
A related word, ${\color{Green}{\text{bore}}}$ can either be a noun or a verb. One can be a bore if he or she lacks energy or enthusiasm, or if he or she seems to take enthusiasm away from others. As a verb, ${\color{Green}{\text{bore}}}$ means to drill a hole, usually into a hard material like metal or rock.
Writing too many things on the ${\color{Red}{\text{board}}}$ while teaching could make the students get ${\color{Purple}{\text{bored}}}$.
Correct Answer $:\text{B}$