Why was mendel successful when others failed?

Using a simple organisms like the garden pea, Mendel was able to control pollination among his experimental plants, and most importantly, he used true breeding plants with easily observable characteristics, such as flower color and height. He also kept meticulous records and discovered consistent data that involved thousands of plant-breeding experiments over eleven years. He studied physics and math under Christian Doppler (1803–1853; the eventual discoverer of the Doppler Effect) at the University of Vienna, which helped Mendel understand statistics and experimentation and eventually led him to determine the laws for his famous heredity works which is why he became successful.

cells use diffusion to get substances in and out of themselves. that diffusion will occur across the cell membrane or the outer covering of the cell. because we are talking about the surface of the cell, surface area and volume are  important factors here. as a cell increases in size, its surface area and volume increase as well.  we call that the surface area to volume ratio (sa: vol).  but the catch is that  volume increases at a greater rate than surface  area. in other words, as a cell gets bigger, the sa: vol gets smaller. so a really small cell like bacteria is mostly cell membrane (surface) with very little contents (volume). a really big cell like an egg, is mostly insides with a super thin membrane. so what ends up happening is that the cell cannot efficiently diffuse all of the stuff it needs in/out to survive. therefore cell size is limited to about 100mm. so how do we make organisms bigger than 100mm? cells divide! by dividing and becoming multicellular, organisms are able to grow!   check out the diagrams i attached to see the effect of sa: vol. i hope this ! good luck!

the answer is c on e2020, bud.