STD 12 - 4. principal of inheritance and variation — BIOLOGY STD 12 Science — Question

$R$ : The linking of antibiotic resistance gene with plasmid vector became possible by enzyme $DNA$ ligase.

$R $ : It requires simultaneous plating on two plates having different antibiotics.

$(A)$ Tropical latitudes have remained relatively undisturbed for millions of years and thus had a long evolutionary
time for species diversification.
$(B)$ Tropical environments are more seasonal and less predictable than temperates.
$(C)$ There is more solar energy available which contributes to higher productivity.