The correct option is
A renovated
Option B: 'Dilapidated' means 'in a state of disrepair or ruin as a result of age or neglect'.
'Renovated' means 'restored to a good state of repair'.
As you can see, 'renovated' means the opposite of 'dilapidated'.
Hence option B is correct.
Option A: 'Furnished' means 'an apartment containing furniture, or complete with furniture'.
Option C: 'Neglected' means 'suffering a lack of proper care'.
Option D: 'Regenerated' means 'bring into renewed existence, generate again'.
These words do not mean the opposite of the italicized word 'dilapidated'.
Hence options A, C and D are wrong.