Increasing order of reactivity towards nucleophilic addition is:
1
Acetophenone < p tolualdehyde < benzaldehyde < p nitro benzaldehyde
2
Acetophenone > p tolualdehyde > benzaldehyde > p nitro benzaldehyde /
3
p tolualdehyde < benzaldehyde < Acetophenone < p nitro benzaldehyde
4
. Acetophenone < benzaldehyde < p tolualdehyde < p nitro benzaldehyde