The alkene is hydrated to form isocitrate, in step 3, the addition of water to form isocitrate is classified as (b) anti-markovnikov addition.
According to Markovnikov's rule when an asymmetrical alkene is attacked by any asymmetrical reagent, then the portion of the reagent having the negative charge will attach to the less hydrogen-containing carbon. while Anti-Markovnikov's rule states that, when an asymmetrical alkene is attacked by any asymmetrical reagent, then the portion of the reagent having the negative charge will attach to the higher hydrogen-containing carbon.
So we can see in the given reaction that, the negative part of the reagent is attached to the carbon having a high number of hydrogen atoms, so it is (b) anti-markovnikov.
The complete reaction mechanism and question are attached.
You can also learn about Markovnikov's rule from the following question:
https://brainly.com/question/28348492
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