Which of the following alkyl groups has the maximum $+I$ effect?

The decreasing order of $-I$ (inductive) effect power for the given groups is:
$A. -CN$
$B. -NO_2$
$C. -NH_2$
$D. -F$

Explain the terms Inductive and Electromeric effects. Which electron displacement effect explains the following correct orders of acidity of the carboxylic acids?
$(a)$ $Cl_3CCOOH > Cl_2CHCOOH > ClCH_2COOH$
$(b)$ $CH_3CH_2COOH > (CH_3)_2CHCOOH > (CH_3)_3C \cdot COOH$

Match the following electronic effects in List-$I$ with their corresponding examples or representations in List-$II$.

List-$I$	List-$II$
$(A)$ Resonance	$(I)$ $C=C + H^+ \rightarrow C^+-C-H$
$(B)$ Inductive effect	$(II)$ $H-CH_2-CH_2^+ \leftrightarrow H-CH_2=CH_2^+$
$(C)$ Electromeric effect	$(III)$ $C_6H_6$
$(D)$ Hyperconjugation	$(IV)$ $CH_3-Z \rightarrow CH_3^- + Z^+$
	$(V)$ $CH_3-CH_2-CH_2Cl$

What is the resonance effect? Write about its types. Or,what is the positive and negative resonance effect? Explain with examples.

Identify the type of electromeric effect ($E$-effect) in the following reactions:
$(a) >C=C< + CN^{-} \to -C(CN)-C^{-}-$
$(b) >C=C< + H^{+} \to -C^{+}-CH-$