Are lipases hydrolases?

[basophilic]

Which class of enzymes is primarily responsible for the release of free glycerol from stored triglycerides?
A) Carboxylases
B) Phosphorylases
C) Lipases
D) Hydrolases

Answer is C. Why isn't D the answer? Don't lipases use water to break the fatty ester linkage?

This was TPR's explanation: "Fatty acid lipases act at specific positions along the glycerol backbone of triglycerides to, in the case of pancreatic lipase, digest dietary triglycerides. Hormone sensitive lipase works similarly, mobilizing stored triglycerides by hydrolysis of the fatty acid-glycerol ester linkage in response to glucagon (choice C is correct). Carboxylases catalyze the decarboxylation of amino acids, β-keto acids and α-keto acids (choice A is wrong). Phosphorylases catalyze the addition of a phosphate group (choice B is wrong) and hydrolases cleave bonds by addition of water (choice D is wrong)."

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[desertrat12]

This is a good question to learn from, and something that seems to be fairly common on the MCAT. Paying close attention to the question stem is the key with this question. It is specifically asking what is responsible for the release of free glycerol. This is the reason the answer is C. Sure they release glycerol through hydrolysis and thus are acting as hydrolases, however in answering these question we are looking for the BEST answer, not just a good answer. If, instead of lipases, the answer for C was transferases, then D is probably the best answer. But lipases specifically release free glycerol. Not all hydrolases release free glycerol, an example of this would be proteases