Which of these is an oxidation-reduction reaction?
A
cap c sub 6 cap h sub 12 cap o sub 6 s plus 6 cap o sub 2 g rightarrow 6 CO sub 2 g plus 6 cap h sub 2 cap o lB
CaCO sub 3 times s rightarrow CaO times s plus CO sub 2 times gC
Ca OH sub 2 s plus cap h sub 2 CO sub 3 l rightarrow CaCO sub 3 times A q plus 2 cap h sub 2 cap o lD
SO sub 2 times g plus cap h sub 2 cap o l rightarrow cap h sub 2 SO sub 3 A q