8.2 Carboxylic acids and their derivative — Chemistry STD 12 Science — Question

$Ni^{2+} | Ni = -0.25\, V$ ;
$Cu^{2+} | Cu = 0.34\, V$
$Ag^+ | Ag = 0.80\, V$ ;
$Zn^{2+} | Zn = -0.76 \,V$
Which of the following reactions under standard condition will not take place in the specified direction 

$(a)\;\left(\mathrm{CH}_{3}\right)_{3} \mathrm{CCH}(\mathrm{OH}) \mathrm{CH}_{3} \stackrel{\mathrm{conc.H}, \mathrm{SO}_{4}}{\longrightarrow}$

$(b)\;\left(\mathrm{CH}_{3}\right)_{2} \mathrm{CHCH}(\mathrm{Br}) \mathrm{CH}_{3} \stackrel{\text { alc.KOH }}{\longrightarrow}$

$(c)\;\left(\mathrm{CH}_{3}\right)_{2} \mathrm{CHCH}(\mathrm{Br}) \mathrm{CH}_{3} \xrightarrow[\text { It should be }\left(\mathrm{CH}_{3}\right)_{3} \mathrm{CO}^{-} \mathrm{K}^{+}]{\text { given by } \mathrm{NTA}\left(\mathrm{CH}_{3}\right)_{3} \mathrm{O}^{-} \mathrm{K}^{+}}$

$(d)\;\begin{array}{*{20}{c}}
  {{{(C{H_3})}_2}C - C{H_2} - CHO} \\ 
  {|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\ 
  {OH\,\,\,\,\,\,\,\,\,\,\,\,\,\,} 
\end{array}\xrightarrow{\Delta }$

Which of these reaction(s) will not produce Saytzeff product ?