Introns in pre-mRNA: a. protect pre-mRNA from enzyme degradation. b. move within the mRNA, giving rise to new exon combinations. c. are spliced out of the message. d. code for important amino acid sequences. e. code for specific protein domains.

c. are spliced out of the message.

Explanation: Intron are non-coding portion of the DNA sequence. They do not code for any specific amino acid and are spliced or removed before splicing.

Exons are DNA sequence that code for specific amino acid they are usually left after introns are removed and are joined together before translation into amino acid sequence. Intron splicing can lead to splicing some exons which can lead to formation of an entirely new amino acid or protein.

Spliceosome are enzymes for splicing introns.

the question isn't complete here so i can't right an answer '_'

the two answers are a, the population of birds with large beaks will increase on the island, and c, the trait for large beaks will be passed on to future generations through natural selection. the reason for that is because if the birds that have beaks developed for eating small seeds lose all of their food, they will go hungry and eventually starve because they physically cannot eat the large seeds, therefore making the population of large beaked birds higher. also, if the trait of large beaks are dominant on the island over small beaks, then over time the large beaked birds will reproduce more and more, while the smaller beaked birds will reproduce less and less because they can't survive with the food provided. that leads to the trait of small beaks disappearing and the trait of large beaks taking over the island.