Which of the following reagents cannot be used to oxidise primary alcohols to aldehydes?

A. \[{{H}_{3}}C\underset{\begin{smallmatrix} \parallel \\ O \end{smallmatrix}}{\mathop{-C-}}\,O{{C}_{2}}{{H}_{5}}\]

B. $${C_2}{H_6}$$

C. $${C_2}{H_4}$$

D. $${C_2}{H_2}$$

A. $${\text{butan - 1 - ol}}$$

B. $${\text{butan - 2 - ol}}$$

C. $${\text{2 - methylpropan - 1 - ol}}$$

D. $${\text{2 - methylpropan - 2 - ol}}$$

A. 1 - pentanol

B. 2 - pentanone

C. 3 - pentanone

D. pentanal

A. ethanol

B. iodoform

C. ethyl iodide

D. methyl iodide