Identify the correct answer.

The correct option is: Three canonical forms can be drawn for $C{O}_3^{2-}$ ion.

Let's evaluate each option step-by-step to understand why this statement is correct and the others are incorrect:
1. Resonance structures of Ozone ($O_3$):
Ozone has only two major canonical (resonance) structures that contribute significantly to its resonance hybrid, not three. Therefore, the first statement is incorrect.

2. Dipole moment of Boron Trifluoride ($B{F}_3$):
$B{F}_3$ has a symmetric trigonal planar geometry. The individual polar B-F bond dipoles point outwards at angles of 120° relative to each other, canceling each other out completely. Consequently, the net dipole moment of $B{F}_3$ is zero. Therefore, the second statement is incorrect.

3. Dipole moments of $N{F}_3$ vs. $N{H}_3$:
In ammonia ($N{H}_3$), the nitrogen atom is more electronegative than hydrogen, so the N-H bond dipoles point towards nitrogen. The lone pair on nitrogen also points in a similar upward direction. The bond dipoles reinforce the lone pair dipole, resulting in a high net dipole moment. In nitrogen trifluoride ($N{F}_3$), fluorine is more electronegative than nitrogen, so the N-F bond dipoles point away from nitrogen, opposing the lone pair dipole. This opposing action significantly reduces the net dipole moment of $N{F}_3$ compared to $N{H}_3$. Hence, the third statement is incorrect.

4. Canonical structures of the Carbonate ion ($C{O}_3^{2-}$):
The carbonate ion has a central carbon atom bonded to three oxygen atoms. The structure consists of one double bond (C=O) and two single bonds (C-O^-) containing negative formal charges. Due to conjugation, the double bond can be shared between the carbon and any of the three oxygen atoms:
- Form 1: The double bond is localized between carbon and oxygen A, with single bonds to oxygens B and C.
- Form 2: The double bond is localized between carbon and oxygen B, with single bonds to oxygens A and C.
- Form 3: The double bond is localized between carbon and oxygen C, with single bonds to oxygens A and B.
These represent exactly three equivalent canonical structures that describe the resonance hybrid of the carbonate ion. Thus, this statement is correct.