Which of the following diseases are known to becaused by viruses? (In this item one or more of the answers given may be correct. Decide which are correct and mark the answer sheet according to the code)
$1.$ Burkitt's lymphoma
$2.$ Adult $T-$ cell leukemia
$3.$ Phenyl ketonuriaCode
$1, 2$ and $3 $ are correct
Only $1$ and $2$ are correct
Only $2$ and $3$ are correct
Only $1$ and $3$ are correct
Natural selection leads to the directional change when
Gill clefts and notochord appear in the embryonic development of all vertebrates from fishes to mammals. This supports the theory of
Assertion : The earliest fossil form in the phylogeny of horse is eohippus.
Reason : Eohippus lived during the early pliocene epoch.