What is the size of the VLAN field inside an 802.1q frame?

A.
8-bit

B.
12-bit

C.
16-bit

D.
32-bit

Explanation:
The VLAN field is a 12-bit field specifying the VLAN to which the frame belongs. The hexadecimal values of 0x000 and 0xFFF are reserved. All other values may be
used as VLAN identifiers, allowing up to 4,094 VLANs
http://en.wikipedia.org/wiki/IEEE_802.1Q