Which of the following sentences uses words most effectively?

a. As we examine our position in relation to supporting the fund drive, it seems that we will be unable to participate at the same level we did in 2004.

b. We won’t be able to give as much to the fund drive as we did in 2004.

c. As we examine our position in relation to supporting the fund drive, it seems that we will be unable to contribute at the same level we did in 2004.

d. As we review our position in relation to supporting the fund drive, it appears that we will be unable to participate at the same level we did in 2004.