Which of the following is a Lyase?: (A) Aldolase, (B) Acetyl Co A Synthetase, (C) Fatty Acyl CoA Dehydrogenase, (D) Acetyl CoA Carboxylase
Answer is A. Lyases: Enzymes specialised in the addition or removal of water, ammonia, CO2 etc.
Some examples of Lyases are:

HMG CoA Lyase
Argininosuccinate Lyase
ATP Citrate Lyase
Aldolase
Fumarase.

Reference- Satyanarayana Pg-87