The number of $\sigma$ and $\pi$ bonds in $2-$formylbenzoic acid are respectively

Explain $\sigma$ bond formed by $s-s$,$s-p$ and $p-p$ overlapping.

Considering the $x$-axis as the internuclear axis,which of the following will not form a sigma $(\sigma)$ bond and why?
$(a)$ $1s$ and $1s$
$(b)$ $1s$ and $2p_{x}$
$(c)$ $2p_{y}$ and $2p_{y}$
$(d)$ $1s$ and $2s$

Given below are two statements :
Statement $(I)$ : The oxidation state of an element in a particular compound is the charge acquired by its atom on the basis of electron gain enthalpy consideration from other atoms in the molecule.
Statement $(II)$ : $p\pi-p\pi$ bond formation is more prevalent in second period elements over other periods.
In the light of the above statements,choose the most appropriate answer from the options given below :

Bond which is formed by sidewise overlapping of $2p$-orbitals of chalcogen atom is present in :

How is the $F_2$ molecule formed?