Refer to the given dichotomous key and select the correct option.
I. (a) Its edible part grows above ground. - Go to II
(b) Its edible part grows below ground. - Go to III
II. (a) It has reticulate venation in leaves - P
(b) It has parallel venation in leaves - Q
III. (a) It has tap root system - R
(b) It has fibrous root system - S
AP could be coriander whereas R could be radish.
BQ could be potato whereas S could be onion.
CQ could be maize whereas R could be wheat.
DP could be mustard whereas S could be pea.