To calculate the charge of each atom.

Formal charge= Valence electrons-(non bonding electron+bonding electron/2)

The possible resonance of CNO- ( check attachment)

The second structure is the most stable because in this structure each atoms carry less formal charge than other.

(a) In the most stable resonance structure of CNO- leftmost bond is a triple bond.

Therefore the statement is False

(b) in the most stable resonance structure of CNO- rightmost bond is single.

Therefore the statement is true

(c) in the most stable resonance

structure of CNO- the formal charge on the leftmost is -1.

Therefore the statement is False

(d) in the most stable resonance structure of CNO-,the number of non bonding electron pairs on the leftmost carbon is 1.

Therefore the statement is False

(e) in the most stable resonance structure of CNO-the number of non bonding electron pairs on rightmost oxygen atom is 3.

Therefore the statement is False