Answer:
a) 妙 -> 劣 -> 加 -> 鳴
妙 MYOU - strange, odd, adroit, mystery
劣 RETSU, oto(ru) - be inferior
加 KA, kuwa(eru), kuwa(waru) - add, append, join, take part
鳴 MEI, na(ku), na(ru)(rasu) - cry, sing, howl, ring
b) 扇 -> 習 -> 皇 -> 現
扇 SEN, oogi - fan
習 SHUU, nara(u) - learn
皇 KOU, OU - emperor
現 GEN, arawa(reru), arawa(su) - present, appear, show