Which of the following is least likely to behave as a Lewis base?

Given below are two statements:
Statement $I$: $F_2O < H_2O < Cl_2O$ is the correct trend in terms of bond angle.
Statement $II$: $SiF_4, SnF_4$ and $PbF_4$ are ionic in nature.

Compound $X$ is the anhydride of sulphuric acid. The number of $\sigma$ bonds and the number of $\pi$ bonds present in $X$ are respectively:

Which of the following statements regarding $BCl_3$ is incorrect?

Choose the correct order for the given properties.

Arrange the following in the decreasing order of their bond enthalpy: $H_2, O_2, N_2$.