Connecting link between ape and man is

The atmosphere became oxidising with the appearance of

Match the following by using codes:

$A.$ Vernalization                         –          $1. $ Camerarius

$B.$ Double fertilization                –          $2.$  Hofmeister

$C.$ Pollination                             –          $3. $ Lysenko

$D.$ Alternation of Generations    –          $4. $ Nawaschin