Once transcribed, eukaryotic mRNA typically undergoes substantial alteration that includes (a) union with ribosome
(b) excision of introns
(c) fusion into circular forms known as plasmids
(d) linkage to histone molecules

B

Explanation:

B describes the RNA processing, which only occurs during eukaryotes and invovles the splicing out of introns and putting together of extrons.

b

Explanation:

succession returns a disturbed

ecosystem to a more stable state. this is also classified into two (2) types:

primary succession and secondary succession. the primary succession arises when

a new land is transformed and a bare rock has been exposed providing an environment

that can be occupied for the first time. while, secondary succession occurs

when a previously occupied environment was disturbed that kills much of all its

community

explanation:

the endomembrane system i think