a CR for discusion

andrewcan

A study of a math program implemented in several pre-schools indicates that children who received the specialized Math Plus math education between the ages three and five had significantly higher math scores in 3rd and 4th grade than their classmates who did not receive this instruction. The proponents of the math argue that the introduction of this program for all children age three to five will significantly improve their chances for success in school.
Which of the following, if true, would most seriously weaken the above argument?

A) Most parents send their children to preschool for social development and do not have a clear idea about what types of education they want for their children.
B) Cognitive abilities of 3- to 5-year-old children are constantly changing.
C) The children in the pre-schools that were studied had previously been exposed to another math enrichment program.
D) Children are not really interested in enrichment programs in preschool.
E) The cost factor needs to be specified and established before a large scale program can be undertaken.


[em13]

raonx

C is the correct answer. there is some other reason that could explain the result.

andrewcan

thanks! another one:

The body of anyone infected by virus X will, after a week, produce antibodies to fight the virus; the antibodies will increase in number for the next year or so. There is now a test that reliably indicates how many antibodies are present in a person's body. If positive, this test can be used during the first year of infection to estimate to within a month how long that person has had the virus.
Which one of the following conclusions is best supported by the statements above?

(A) Antibodies increase in number only until they have defeated the virus.
(B) Without the test for antibodies, there is no way of establishing whether a person has virus X.
(C) Antibodies are produced only for viral infections that cannot be fought by any other body defenses.
(D) If a person remains infected by virus X indefinitely, there is no limit to the number of antibodies that can be present in the person's body.
(E) Anyone infected by virus X will for a time fail to exhibit infection if tested by the antibody test.

andrewcan

In fact, E is better.