(fill in the blanks)

in the figure, cd = ef and ab = ce. complete the statements to prove that ab = df.
cd + de = ef + de by the ( property of equality.
ce = cd + de and df = ef + de by (
ce = df by the ( property of equality.
given, ab = ce and ce = df implies ab = df by the ( property of equality.

options for number one:
a. addition
b. subtraction
c. substitution
d. transitive

options for number two:
a. addition
b. subtraction
c. segment addition
d. transitive

options for number three:
a. addition
b. subtraction
c. substitution
d. transitive

options for number four:
a. addition
b. subtraction
c. substitution
d. transitive