Which of the following is the most correct electron displacement for a nucleophilic reaction to take place?

$+I$ effect is shown by:

The functional group that shows negative resonance effect ($-R$ effect) is:

Find the compound that has the maximum enol content.

State True or False for the following statements:
$(i)$ The stability is explained by resonance effect and hyperconjugation.
$(ii)$ The resonance structures are drawn in resonance and hyperconjugation.
$(iii)$ Hyperconjugation is a bondless resonance.
$(iv)$ In resonance structure,there is movement of electron pair of only $\pi$ bond.

The decreasing order of acidity of the following terminal acetylenes is: