The book To Save the Earth is so persuasive that no one who reads it

Premise - everyone will heed the message (Fact)
Conclusion - The Earth Association can justly claim credit for at least 2,000 people in one month converted to the environmentalist cause.

Possible assumption(s)
Will all 2k people embrace it?

A - not concerned about other org.
B - we cant derive a correlation saying if someone who pays for it will definitely read it
C - printed on recycled paper does not matter

D- Leave it in. Ex - if 2k were not committed and on reading the book, they get persuaded to commit to the cause, then the company's claim is valid.

E - Hits the assumption. Leave it in.

hmm..? tough choice between D and E
but wait if we observe the premise carefully, it clearly states that the book is so "persuasive" that any one who reads it would definitely heed the cause. Hence, the earlier stated assumption(Will all 2k people embrace it?) can be neglected.

Consider a negation technique for D
Some or All those who received the book were already committed to the cause, say 500. This implies the remaining 1500 were persuaded to commit to the cause after reading the book, hence the conclusion - "atleast" 2k people have converted to the envt cause fails because only 1500 did(1500<2000), fails.

Answer : D