There are three common ways to convert an alkene into alcohol: a) acid catalysed hydration, b)hydroboration -oxidation and c)oxymercuration-demercuration. Which of the following statements about these reactions is correct?

Question

$\begin{array}{1 1}a)\; B\; results\; in\; the \;syssterochmistry \;of\; -H \;and\; -OH \;groups, while\; A\; and \;C\; show\; no \;clear\; stereochemical \;preference.\\b)\; A \;and\; C\; gives\; Markovnikov's\; products, while\; B results\; in\; anti- Markovnikov's \;regioselectivity.\\c)\; Carbocation\; rearrangements\; are \;observed\; in\; A, but\; unrearranged \;products\; are \;obtained\; from \;B \;and \;C.\\d)\; In\; all \;three\; reactions, water\; serves\; as\; nucleophile.\end{array}$