The typical estimation of Zeff only counts core electrons as shielding electrons. For a more accurate estimation of Zeff, the other electrons that are not core electrons also have to be considered. These electrons also contribute to shielding, but not to the full extent as core electrons and can be estimated as a shielding of 0.35 each. For example: what is the effective nuclear charge of a valence electron in C

answer: they produce more slow than unicellular organisms.

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.

the answer your looking for is c).