I will go with C.
Premise: Trait X is due to Heridity. Trait Y is due to environment.
Assumption: A given trait is
ENTIRELY due to
EITHER heridity
OR environment. (Mutually Exclusive)
(A) Fewer than half of the pairs of twins studied were raised separately.
--> If the assumption above is accepted, the size of the group doesn't matter.
(B) The ages of all of the twins studied fell within a 10-year range. -
-> Out of scope (OOS) - Age doesn't matter-
(C) Some of the traits that the study attributed to heredity developed in the separately raised twins because those pairs all grew up in similar families. -->
ATTACKS MY ASSUMPTION.
MY ARGUMET IS FALLING APART! HELP!
(D) Although over half the traits measured were determined to be linked to heredity, the nature of those traits varied widely.
--> OOS - Nature of the traits is not an issue
(E) The 11 traits that were measured constitute a representative sample of larger, generally accepted pool of key personality traits
---> OOS - Type of trait is not an issue.
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