a. War:Death
b. Water: River
C. Iron:Strength
d. Vaccination:Immunity
e. Degeneration:Decay
Is d the correct answer?

I have no idea. If you ever discover the answer to this – and, more importantly, the reason – please let us know!

b) and c) don’t fit in.[YSaerTTEW443543]

TOEIC listening, talks: A weather forecast for a coastAL region[YSaerTTEW443543]