Which of the following diatomic molecular species has only `pi` bonds according to Molecular orbital Theory

Which of the following diatomic molecular species has only pi at bonds according to molecular orbital theory?

According to molecular arbital theory,

Which one of the following molecular species has the highest bond order ?

Chemical Bonding - Molecular Orbital Theory

In accordance to molecular theory,

Chemical Bonding - Molecular Orbital Theory (2)

Chemical Bonding - Molecular Orbital Theory (3)