In which of the following transformations,the bond order has increased and the magnetic behaviour has changed?

The difference between bond orders of $CO$ and $NO^{\oplus}$ is $\frac{x}{2}$ where $x = .....$
(Round off to the Nearest Integer)

Identify a molecule which does not exist.

The bond order and magnetic property of acetylide ion are same as that of $........$.

Bond order of $He_{2}$,$He_{2}^{+}$ and $He_{2}^{2+}$ are respectively:

Given below are two statements:
Statement $I$: $A$ hypothetical diatomic molecule with bond order zero is quite stable.
Statement $II$: As bond order increases,the bond length increases.
In the light of the above statements,choose the most appropriate answer from the options given below.