To answer the question about the common features among the species CN^-, CO, and NO⁺, let's first understand the electronic configurations and bond orders of each species.

1. Electronic Configurations:

- CN^-: The cyanide ion (CN^-) has an electronic configuration similar to N₂ because CN has 10 electrons (from C and N); adding one more electron for the negative charge brings it to 11 electrons.

- CO: Carbon monoxide (CO) has a total of 10 valence electrons (4 from Carbon and 6 from Oxygen).

- NO⁺: The nitrosonium ion (NO⁺) has a total of 10 electrons as well, considering the positive charge removes one electron from the original 11 valence electrons of NO.

Thus, all three species CN^-, CO, and NO⁺ are isoelectronic, meaning they all have the same number of electrons (10 valence electrons).

2. Bond Order: The bond order is the number of chemical bonds between a pair of atoms. It is calculated as half the difference between the number of bonding electrons and the number of antibonding electrons. All three species have a bond order of 3, as can be seen from their molecular orbital diagrams.

3. Ligand Field Strength:

CO and CN^- are generally considered strong field ligands due to their ability to partake in back-donation, where electrons from the metal center can be donated back into the empty π* orbitals of the ligand. NO⁺ is also a reasonably strong field ligand due to its ability to accept electrons.

Conclusion:

Based on the above analysis, the correct option is:

Option A: bond order three and isoelectronic

This option accurately describes the common features among CN^-, CO, and NO⁺.