Re: The Missouri Compromise of 1820, a legislative effort to

a. just the first of more than a half-dozen attempts to avert
b. just the first of a half-dozen more attempts to avert
c. and the first attempt of more than a half-dozen attempts to avert
d. and just the first of more than a half-dozen attempts averting
e. and just the first of more than a half-dozen attempts aimed at averting

B-->change in meaning
C-->redundant...first attempt of more than ___ attempts? why not just say first of a few attempts
D-->attempts averting...wrong idiomatic structure
E-->attempts aimed at...again wrong idiomatic structure. You attempt TO do something.