Self-study
Conclusion The ability of mammals to control their internal body temperatures is a factor in the development of their brains and intelligence. ████ ███ ██ ████ ████ ███ █████████ ██████ ███ █████ ██ █ ████████ ████████ ███ ████████ █████████ ███ ███████████ ██████████ ███ ███ ████████ ████ ███ ███████ ███ ████ ███████████ ███ ██████ ████ █████ █████████ █████ ██ ███ ██████ █████████████
Summary
Mammals’ temperature-controlling ability factors into the development of their brain and intelligence. Why? Because brains are chemical, chemical reactions depend on temperature, and mammals are able to assure those reactions happen at the appropriate temperature.
Notable Assumptions
The author tries to use the fact that mammals can assure chemical reactions are happening at the right temperature as support, but her conclusion is about development of the brain and intelligence. We need to know these these two things (temperature-controlled chemical reactions and development of brain and intelligence) are related.
20.
Which one of the following ██ ██ ██████████ ██ █████ ███ ████████ ████████
a
Organisms unable to ███████ █████ ████ ████████████ ██ ███ ████ ███ ████████ ██ ████████ ████████ ████ ████ ███████ ███████ ██ ████████ ████████
Irrelevant. We don’t need information about organisms without this ability. The argument is about mammals, and they do have this ability.
b
Mammals are the ████ ███████ ████ ████ ███ ███████ ██ ███████ █████ ████████ ████ █████████████
The conclusion is specific to mammals, but it isn’t necessary that mammals are the only ones with this ability.
c
The brain cannot ███████ ████████████ ██ ███ ████████ █████████ ██████ ██ ███ ███████ ██ ████████████ █████████████
Similar to (A), we do not need information about uncontrolled temperature or organisms without this ability. The argument is about mammals that can control temperatures.
d
The development of ████████████ ██ ███████ ██ ███ ███████████ ██ ███ ████████ █████████ ██ █████ ██████ ██████ █████ ██ ███ ██████ █████████████
This must be true. If negated, the development of intelligence has nothing to do with the chemical reactions that mammals can temperature-control. The premises would be severed from the conclusion, and the argument is ruined.
e
Organisms incapable of ███████████ █████ ████████ ████ ████████████ ███ ███████ ██ █████████████ ████████ ██████████
Like (A) and (C), we do not need information about organisms without this ability. It isn’t necessary or relevant to the argument; we are discussing mammals that do have this ability.