As we know that ,
Tirade is a formal and strong criticism, Censure, declamation and discredit are synonymous to Tirade, analogy means excessive praise.

Correct Option: D

As we know that ,
Tirade is a formal and strong criticism, Censure, declamation and discredit are synonymous to Tirade, analogy means excessive praise.
Thus , Eulogy is opposite word of Tirade .

As we know say that ,
Transient is what doesn’t last forever, i.e. what is not permanent. Transitory, fleeting, momentary all means the same as transient.

Correct Option: C

As we know say that ,
Transient is what doesn’t last forever, i.e. what is not permanent. Transitory, fleeting, momentary all means the same as transient.
Therefore ,Permanent is an opposite word of Transient .

As we can say that ,
Partition is to divide,
unify is to bring together,
Enjoin means command or an order.

Correct Option: C

As we can say that ,
Partition is to divide,
unify is to bring together,
Enjoin means command or an order.
Therefore , unify is an opposite of Partition .

As we know that ,
Smother means to suffocate or stifle, i.e, to prevent the growth of something, nurture is to help the growth, repress also means to prevent the growth and thus is a synonym to smother.

Correct Option: C

As we know that ,
Smother means to suffocate or stifle, i.e, to prevent the growth of something, nurture is to help the growth, repress also means to prevent the growth and thus is a synonym to smother.
From above it is clear that Nurture is opposite word of Smother .

As we can say that ,
Nebulous is indistinct something that does not have a clear outline, Concrete is solid and of definite shape.

Correct Option: A

As we can say that ,
Nebulous is indistinct something that does not have a clear outline, Concrete is solid and of definite shape.
Hence , Concrete is antonym ( opposite ) of Nebulous .