What sequence of steps represents the best synthesis of 4-heptanol `(CH_(3)CH_(2)CH_(2))_(2)CHOH` ?

Options

A. `CH_(3)CH_(2)CH_(2)MgBr` (2 moles) + formaldehyde `(H_(2)C=O)` in diethyl ether followed by `H_(3)O^(+)`.
B. `CH_(3)CH_(2)CH_(2)MgBr` + butanol `(CH_(3)CH_(2)CH_(2)CH=O)` in diethyl ether followed by `H_(3)O^(+)`
C. `CH_(3)CH_(2)CH_(2)CH_(2)MgBr` + acetone `[(CH_(3))_(2)C=O]` in diethyl ether followed by `H_(3)O^(+)`
D. `(CH_(3)CH_(2)CH_(2))_(2)CHMgBr` + formaldehyde `(H_(2)C=O)` in diethyl ether followed by `H_(3)O^(+)`

Answer

B

Explanation

Gives 1-Butanol as the product
(c) Gives 2-methyl-2-hexanol as the product
(d) Gives 2-propyl-1-pentanol as the product
only (b) gives 4-heptanol as the product.