$\mathbf{a})$  

$\stackrel{-III}{C}{H}_3-\stackrel{-I}{C}H=\stackrel{+I}{C}Cl-\stackrel{0}{C}H\left(OH\right)-\stackrel{+III}{C}OOH$

$\mathbf{b})$   

$Br-\stackrel{-I}{C}{H}_2-\stackrel{-II}{C}{H}_2-\stackrel{0}{C}H\left(OH\right)-\stackrel{+III}{C}OOH$

 

$\mathbf{c})$  

$\stackrel{-I}{C}H\equiv \stackrel{0}{C}-\stackrel{+II}{C}O-\stackrel{+III}{C}ON{H}_2$

 

$\mathbf{d})$  

$\stackrel{0}{C}{H}_{2}BrCl$