High Homocysteine Levels Are Associated with an Increased Risk of Atherosclerosis.A

High homocysteine levels are associated with an increased risk of atherosclerosis.A deficiency of which of the following enzymes would result in high blood levels of homocysteine (and also methionine) ?

A) Tyrosine hydroxylase.
B) Cystathionine synthase.
C) Threonine dehydratase.
D) Glutathione reductase.
E) L-Amino acid oxidase.