Al johnson develops condominium communities in central florida for the senior living market. in a recent development project, al found he continually added square footage and features to the units, causing considerable delays and added expense. al's rationale is consistent with the idea of

i would say b. research typically uses a variety of sources

good question. i'll be looking into that. (this is a joke sir)

d. i assume the underlined word is "role." reformat if it isn't.

explanation:

role is closest to part because when replacing words, "playing a vital decision," "playing a vital activity," and "playing a vital dollar" don't make logical sense. the only meaningful choice is "playing a vital part."

this fits one of merriam-webster's definitions of role: "a function or part performed especially in a particular operation or process."

d

explanation:

it establishes america’s basic laws and fundamentals to its citizens.