Watson and Crick built a DNA model demonstrating that:

the answer would be   10%

the correct answer is option d.

an appositive is a noun, noun phrase or noun clause which follows another noun or noun phrase in order to describe it or name it another way. they are usually used between commas, brackets or dashes.

the example sentence with the correct use of commas is the following:

her uncle, the man over there in the red shirt, owns the hardware store in town.

it is because according to the process , scientific inquiry is a process with many steps because each step occurs to the scientist and if you just skip a step there would be no steps to scientific inquiry.