Find out the odd one.

Who worked on embryological aspects and popularized the use of embryological characters in taxonomy?

What is the viability period of pollen grains in members of the families $Rosaceae$,$Leguminosae$,and $Solanaceae$?

How many times will meiosis take place for the formation of $80$ wheat grains?

Which organism possesses the highest number of chromosomes?

Which of the following statement$(s)$ is/are correct for cleistogamous flowers?
$(a)$ They have exposed anthers and stigma
$(b)$ They produce assured seed set
$(c)$ They need pollinators for pollination
$(d)$ Variations in traits are not seen in next generation