The prefix sub- means under. Someone who is "submissive" is someone who likes to be controlled by someone else, someone under control. The closest word to this is "obedient" which means someone who does what they are told. To provide further help, "hostile" means not friendly, threatening; "dominant" means in-charge, it is opposite in meaning to "submissive"; "frenetic" means chaotic and fast-paced; "unusual" means weird, not normal.

The prefix mal- means bad so you can reasonably infer that the correct answer must mean something bad. Something that is "malignant" is deadly, bad for you and dangerous. To provide further help, "benign" means not malignant, not deadly, harmless; "unkempt" means messy; "scarce" means rare, in short supply. 

The prefix proto- means first. So, a "prototype" is an early or first model of something. Additionally, "elementary" means basic, not complicated. 

The prefixes dys- and dis- means not. As in "dislike" which means to not like. Furthermore, "functional" means working properly. So, "dysfunctional" means not working. This is closest in definition to "broken." Additionally, "precious" means treasured, very special and important to; "literate" means able to read and write; "plucky" means courageous, brave, usually it describes someone small who is braver than might be expected; "repaired" means fixed.

The prefix morph- means shape. So, to "morph" literally means to change shape. Additionally, "suffer" means feel pain; "rejoice" means celebrate, draw happiness from; "unite" means bring together, join, connect; "preach" means deliver a speech to a group of people, particularly a religious message. 

The prefixes con-, and com- mean with, together. As in "convene," which means meet, come together to discuss. So, "compact" means something like pushed together or "dense." If you need further help, "dense" means thick, tightly packed together.

The prefix re- means back or again. As in "respond," which means say something back, in reply. So, "reflect" means to think back on. This is closest in meaning to "consider." Additionally, "supplant" means replace; "discuss" means talk about; "acknowledge" means recognize, notice. 

The prefix fore- means before. As in "forerunner," which means something that comes before something else. So, to "foretell" means to predict, to warn. All the other answer choices are things you do after an event. So, for example, "revert" means to change back to an earlier state.

The prefix arm- means weapon, war. As in "disarm," which means to make safe, to take a weapon away from. So, "arms" are weapons or weaponry. Additionally, "society" is the name given to a group of people; "philosophy" is the study of the essential nature of things, literally the love of wisdom; "anatomy" is the area of science that studies the body structure of living beings.

The prefix therm- means hot, heat. As in "thermometer," which is something used to measure temperature. "Thermal" means related to heat, so the best answer choice here is of course "heat." Additionally, "mass" refers to the weight of something (in the science classroom the definition is a little more complicated, but for the purposes of practical vocabulary "mass" and "weight" are the same). Finally, "velocity" refers to speed.