While trying to learn what a "dog" is, Arash mentally compares every animal to his family's new puppy. If the animal is similar enough, he decides that it is also a dog. Arash's puppy serves as a for the concept of "dog."
A) proposition
B) heuristic
C) concept
D) prototype

D. Prototype

Explanation: A prototype could be seen as a canvas, design or knowledge upon which future designs or knowledge patterns are based. It could be the original version of something or object upon which future development or concept related to such objects are based.

In the scenario above, Arash uses his family's new puppy as a prototype in his bid to learn what a 'dog' is by mentally comparing any animal to the puppy. The puppy was used as a basis for developing the knowledge of what a dog is.

this null effect is caused by a weak manipulation and ineffective internal validity. in a scientific study, as the one dr. morimoto is trying to perfom, internal validity refers to the confidence placed in the cause-effect relationship and to how well an experiment is done and able to eliminate confounding variables.        

the earth’s crust is broken into separate pieces called tectonic plates (fig. 7.14). recall that the crust is the solid, rocky, outer shell of the planet. it is composed of two distinctly different types of material: the less-dense continental crust and the more-dense oceanic crust. both types of crust rest atop solid, upper mantle material. the upper mantle, in turn, floats on a denser layer of lower mantle that is much like thick molten tar.

each tectonic plate is free-floating and can move independently. earthquakes and volcanoes are the direct result of the movement of tectonic plates at fault lines. the term fault is used to describe the boundary between tectonic plates. most of the earthquakes and volcanoes around the pacific ocean basin—a pattern known as the “ring of fire”—are due to the movement of tectonic plates in this region. other observable results of short-term plate movement include the gradual widening of the great rift lakes in eastern africa and the rising of the himalayan mountain range. the motion of plates can be described in four general patterns:

collision: when two continental plates are shoved together

subduction: when one plate plunges beneath another (fig. 7.15)

spreading: when two plates are pushed apart (fig. 7.15)

transform faulting: when two plates slide past each other (fig. 7.15)