The highlighted word means 'lessened' or 'eased'.
Option A is correct. 'Relieved', in this context, means 'lessened'. Since it has the required meaning, it is the correct answer.
Options B, C and D are incorrect. They do not have the required meaning.
'Obliterated' means 'completely destroyed', 'aroused' means 'excited' and 'eradicated' means 'eliminated' or 'wiped out'.