Which scientist did not contribute to the rediscovery of Mendel's results?

Mendel's work remained unrecognized for a long time due to:
$I.$ Communication was not easy.
$II.$ The concept of factors which did not blend was not accepted.
$III.$ The use of mathematics to explain biological problems was unacceptable.
$IV.$ He could not provide any physical proof for the existence of factors.
Choose the right combination.

The principles or laws of inheritance were enunciated by:

Define/Explain the following terms:
$1.$ Offspring
$2.$ Phenotype

Which of the following traits was $NOT$ selected by Mendel in his pea plant experiments?

The number of contrasting characters studied by Mendel for his experiments was