I don't know witch definition you mean, but here: https://www.google.com/search?q=google+dictionary&rlz=1C1CHBF_enUS871US871&oq=google+dic&aqs=chrome.0.0j69i57j0l6.3972j0j7&sourceid=chrome&ie=UTF-8#dobs=blowout
The main difference between prokaryotes and eukaryotes is the presence of nucleus in eukaryotes and its absence in prokaryotes. Also, prokaryotes are unicellular, so one cell is a whole organism. On the other hand, eukaryotes are mainly multicellular, and thus more complex. More complex DNA is inside the nucleus in the eukaryotes which enables them to conduct a wider range of functions. Prokaryotes, as a single cell, have simple functions present.
I think d is the correct answer or not