The cell membrane a) is also referred to as the plasma membrane
b) The movement of particles is always passive
c) is a rigid structure
d) is a fluid mosaic
e) is made up of proteins and lipid

a) plasma membrane

Explanation:

answer: land bridge theory. land bridge theory held that shifting portions of dry land explained the finding of identical species on different continents. plate tectonic theory eventually eliminated the land bridge theory.

i think its both a and b