Which sentence from the text best illustrates the message of this speech?
a) "now is the time to make justice a reality for all of god's children."
b) "it came as a joyous daybreak to end the long night of their captivity."
c) "we refuse to believe that there are insufficient funds in the great vaults of opportunity of this nation."
d) "five score years ago, a great american, in whose symbolic shadow we stand today, signed the emancipation proclamation."