Stings of honey bee and the stings of scorpion are
$I.$ analogous organs
$II.$ heterologous organs
$III.$ homologous organs
$IV.$ vestigial organs
The correct combination is
$III$ and $IV$
$II$ and $III$
$I$ and $II$
$I$ and $III$
Cycas and Ginkgo are connecting links between
Ornithorhynchus is a connecting link between
$A$ : Due to bottle neck effect, among the survivors, certain alleles may be over represented, some may be underrepresented and some alleles may be totally eliminated.
$R$ : The path of extinction of a species cannot be reversed due to bottle neck effect