Concept:
Colour of fruits and vegetables is mainly due to different pigments such as lycopene, chlorophyll, carotenoids and anthocyanins.
Step 1: Match Lycopene.
Lycopene gives red colour to tomato.
\[
A\rightarrow I
\]
Step 2: Match Chlorophyll.
Chlorophyll gives green colour to cucumber.
\[
B\rightarrow II
\]
Step 3: Match Carotenoid.
Carotenoids give yellow-orange colour to mango.
\[
C\rightarrow III
\]
Step 4: Match Anthocyanin.
Anthocyanin gives purple or dark colour to fruits like jamun.
\[
D\rightarrow IV
\]
Therefore:
\[
A-I,\ B-II,\ C-III,\ D-IV
\]
\[
\therefore \text{Correct Answer is (A)}
\]