Volvox, the green algae illustrated here, is considered a colony. yet some scientists argue that it is more like a multicellular life form. in order for a cell or group of cells to evolve into a multicellular organism, all but one of these events must occur. that is
a cells are bound together
b cells specialize and cooperate
c cells form a protective outer sheath
d cells have like pairs of chromosomes

The correct answer is B- cells specialize and cooperate

Explanation:

A unicellular organism is made up of single-cell and this single cell performs all the function to make the organism live and multicellular organisms are made up of multiple cells that are organized and each cells are specialized for performing a particular function and each cell in a structure cooperated each other to support the organism.

Therefore for a cell or group of cells to evolve in a multicellular organism, the cells must be specialized to perform different functions and should cooperate each other to perform these functions.

Volvox can live in colonies which can have 50,000 cells but they are unicellular because each cell is not specialized to perform different function.

•there must be variation for the particular trait within a population.

•the variation must be inheritable (that is, it must be capable of being passed on from the parents to their offspring).

•individuals with one version of the trait must produce more offspring than those with a different version of the trait.good

explanation:

straight or amphibians are homeothermic to thermal