Is the relation "$A$ is r.e. (recursively enumerable) relative to $B$" transitive?

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I wonder if $A$ r.e. (recursively enumerable) relative to $B$ is transitive. Here I say relative to means $A$ is the domain of some partial function that is recursive in B. Intuitively, I think it is not transitive but I simply can not find a proper counter-example...

Please offer some help, thank you.