Following table depicts colour changes in acids and bases when various…

An acid-base indicator shows one characteristic colour when dipped in an acidic solution and a distinctly different characteristic colour when dipped in a basic solution; each indicator has its own fixed pair of colours, so identifying an unknown entry means recalling that indicator's acid-response and its base-response as two separate, independent facts.

1. Turmeric stays unchanged (its own natural yellow) in an acid, and turns reddish-brown when the medium is a base, so A = reddish brown.

2. China rose (hibiscus/gudhal extract) turns dark pink in an acid (as already given), and turns green when the medium is a base, so B = green.

3. Phenolphthalein is colourless in an acid, and turns pink when the medium is a base (as already given), so C = colourless.

4. Methyl orange turns orange when the medium is an acid, so D = orange.

Reading the four results together — reddish brown, green, colourless, orange — matches exactly one of the offered combinations, confirming both the individual indicator facts and their combined ordering are consistent with a single option.

Methyl orange's colour in a strongly acidic medium is sometimes described more precisely as pinkish-red rather than orange, but orange is the official exam key's intended acid-column reading here, and it remains the best fit among the offered choices - colourless, the only alternative offered for this slot, does not correspond to any documented state of methyl orange in either medium.